Quelle  BrowserParent.cpp   Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "base/basictypes.h"

#include "BrowserParent.h"
#include "mozilla/AlreadyAddRefed.h"
#include "mozilla/EventForwards.h"

#ifdef ACCESSIBILITY
#  include "mozilla/a11y/DocAccessibleParent.h"
#  include "mozilla/a11y/Platform.h"
#  include "nsAccessibilityService.h"
#endif
#include "mozilla/Components.h"
#include "mozilla/dom/BrowserHost.h"
#include "mozilla/dom/BrowserSessionStore.h"
#include "mozilla/dom/BrowsingContextGroup.h"
#include "mozilla/dom/CancelContentJSOptionsBinding.h"
#include "mozilla/dom/ChromeMessageSender.h"
#include "mozilla/dom/ContentParent.h"
#include "mozilla/dom/ContentProcessManager.h"
#include "mozilla/dom/DataTransfer.h"
#include "mozilla/dom/DataTransferItemList.h"
#include "mozilla/dom/DocumentInlines.h"
#include "mozilla/dom/Event.h"
#include "mozilla/dom/indexedDB/ActorsParent.h"
#include "mozilla/dom/PaymentRequestParent.h"
#include "mozilla/dom/PContentPermissionRequestParent.h"
#include "mozilla/dom/PointerEventHandler.h"
#include "mozilla/dom/BrowserBridgeParent.h"
#include "mozilla/dom/RemoteDragStartData.h"
#include "mozilla/dom/RemoteWebProgressRequest.h"
#include "mozilla/dom/SessionHistoryEntry.h"
#include "mozilla/dom/SessionStoreParent.h"
#include "mozilla/dom/UserActivation.h"
#include "mozilla/EventStateManager.h"
#include "mozilla/gfx/2D.h"
#include "mozilla/gfx/DataSurfaceHelpers.h"
#include "mozilla/gfx/GPUProcessManager.h"
#include "mozilla/IMEStateManager.h"
#include "mozilla/ipc/Endpoint.h"
#include "mozilla/layers/AsyncDragMetrics.h"
#include "mozilla/layers/InputAPZContext.h"
#include "mozilla/layout/RemoteLayerTreeOwner.h"
#include "mozilla/LookAndFeel.h"
#include "mozilla/Maybe.h"
#include "mozilla/MiscEvents.h"
#include "mozilla/MouseEvents.h"
#include "mozilla/NativeKeyBindingsType.h"
#include "mozilla/net/NeckoChild.h"
#include "mozilla/net/CookieJarSettings.h"
#include "mozilla/Preferences.h"
#include "mozilla/PresShell.h"
#include "mozilla/ProcessHangMonitor.h"
#include "mozilla/RecursiveMutex.h"
#include "mozilla/RefPtr.h"
#include "mozilla/StaticPrefs_dom.h"
#include "mozilla/TextEventDispatcher.h"
#include "mozilla/TextEvents.h"
#include "mozilla/TouchEvents.h"
#include "mozilla/UniquePtr.h"
#include "mozilla/Unused.h"
#include "nsCOMPtr.h"
#include "nsContentPermissionHelper.h"
#include "nsContentUtils.h"
#include "nsDebug.h"
#include "nsFocusManager.h"
#include "nsFrameLoader.h"
#include "nsFrameLoaderOwner.h"
#include "nsFrameManager.h"
#include "nsIBaseWindow.h"
#include "nsIBrowser.h"
#include "nsIBrowserController.h"
#include "nsIContent.h"
#include "nsICookieJarSettings.h"
#include "nsIDocShell.h"
#include "nsIDocShellTreeOwner.h"
#include "nsImportModule.h"
#include "nsIInterfaceRequestorUtils.h"
#include "nsILoadInfo.h"
#include "nsIPromptFactory.h"
#include "nsIURI.h"
#include "nsIWebBrowserChrome.h"
#include "nsIWebProtocolHandlerRegistrar.h"
#include "nsIWindowWatcher.h"
#include "nsIXPConnect.h"
#include "nsIXULBrowserWindow.h"
#include "nsIAppWindow.h"
#include "nsLayoutUtils.h"
#include "nsQueryActor.h"
#include "nsSHistory.h"
#include "nsViewManager.h"
#include "nsVariant.h"
#include "nsIWidget.h"
#include "nsNetUtil.h"
#ifndef XP_WIN
#  include "nsJARProtocolHandler.h"
#endif
#include "nsPIDOMWindow.h"
#include "nsPrintfCString.h"
#include "nsQueryObject.h"
#include "nsServiceManagerUtils.h"
#include "nsThreadUtils.h"
#include "PermissionMessageUtils.h"
#include "StructuredCloneData.h"
#include "ColorPickerParent.h"
#include "FilePickerParent.h"
#include "BrowserChild.h"
#include "nsNetCID.h"
#include "nsIAuthInformation.h"
#include "nsIAuthPromptCallback.h"
#include "nsAuthInformationHolder.h"
#include "nsICancelable.h"
#include "gfxUtils.h"
#include "nsILoginManagerAuthPrompter.h"
#include "nsPIWindowRoot.h"
#include "nsReadableUtils.h"
#include "nsIAuthPrompt2.h"
#include "gfxDrawable.h"
#include "ImageOps.h"
#include "UnitTransforms.h"
#include <algorithm>
#include "mozilla/NullPrincipal.h"
#include "mozilla/WebBrowserPersistDocumentParent.h"
#include "ProcessPriorityManager.h"
#include "nsString.h"
#include "IHistory.h"
#include "mozilla/dom/WindowGlobalParent.h"
#include "mozilla/dom/CanonicalBrowsingContext.h"
#include "mozilla/ProfilerLabels.h"
#include "MMPrinter.h"
#include "mozilla/dom/CrashReport.h"
#include "nsISecureBrowserUI.h"
#include "nsIXULRuntime.h"
#include "VsyncSource.h"
#include "nsSubDocumentFrame.h"

#ifdef XP_WIN
#  include "FxRWindowManager.h"
#endif

#if defined(XP_WIN) && defined(ACCESSIBILITY)
#  include "mozilla/a11y/AccessibleWrap.h"
#  include "mozilla/a11y/Compatibility.h"
#  include "mozilla/a11y/nsWinUtils.h"
#endif

#ifdef MOZ_GECKOVIEW_HISTORY
#  include "GeckoViewHistory.h"
#endif

#if defined(MOZ_WIDGET_ANDROID)
#  include "mozilla/widget/nsWindow.h"
#endif  // defined(MOZ_WIDGET_ANDROID)

using namespace mozilla::dom;
using namespace mozilla::ipc;
using namespace mozilla::layers;
using namespace mozilla::layout;
using namespace mozilla::services;
using namespace mozilla::widget;
using namespace mozilla::gfx;

using mozilla::LazyLogModule;

extern mozilla::LazyLogModule gSHIPBFCacheLog;

LazyLogModule gBrowserFocusLog("BrowserFocus");

#define LOGBROWSERFOCUS(args) \
  MOZ_LOG(gBrowserFocusLog, mozilla::LogLevel::Debug, args)

/* static */
BrowserParent* BrowserParent::sFocus = nullptr;
/* static */
BrowserParent* BrowserParent::sTopLevelWebFocus = nullptr;
/* static */
BrowserParent* BrowserParent::sLastMouseRemoteTarget = nullptr;

// The flags passed by the webProgress notifications are 16 bits shifted
// from the ones registered by webProgressListeners.
#define NOTIFY_FLAG_SHIFT 16

namespace mozilla {

/**
 * Store data of a keypress event which is requesting to handled it in a remote
 * process or some remote processes.
 */
class RequestingAccessKeyEventData {
 public:
  RequestingAccessKeyEventData() = delete;

  static void OnBrowserParentCreated() {
    MOZ_ASSERT(sBrowserParentCount <= INT32_MAX);
    sBrowserParentCount++;
  }
  static void OnBrowserParentDestroyed() {
    MOZ_ASSERT(sBrowserParentCount > 0);
    sBrowserParentCount--;
    // To avoid memory leak, we need to reset sData when the last BrowserParent
    // is destroyed.
    if (!sBrowserParentCount) {
      Clear();
    }
  }

  static void Set(const WidgetKeyboardEvent& aKeyPressEvent) {
    MOZ_ASSERT(aKeyPressEvent.mMessage == eKeyPress);
    MOZ_ASSERT(sBrowserParentCount > 0);
    sData =
        Some(Data{aKeyPressEvent.mAlternativeCharCodes, aKeyPressEvent.mKeyCode,
                  aKeyPressEvent.mCharCode, aKeyPressEvent.mKeyNameIndex,
                  aKeyPressEvent.mCodeNameIndex, aKeyPressEvent.mKeyValue,
                  aKeyPressEvent.mModifiers});
  }

  static void Clear() { sData.reset(); }

  [[nodiscard]] static bool Equals(const WidgetKeyboardEvent& aKeyPressEvent) {
    MOZ_ASSERT(sBrowserParentCount > 0);
    return sData.isSome() && sData->Equals(aKeyPressEvent);
  }

  [[nodiscard]] static bool IsSet() {
    MOZ_ASSERT(sBrowserParentCount > 0);
    return sData.isSome();
  }

 private:
  struct Data {
    [[nodiscard]] bool Equals(const WidgetKeyboardEvent& aKeyPressEvent) {
      return mKeyCode == aKeyPressEvent.mKeyCode &&
             mCharCode == aKeyPressEvent.mCharCode &&
             mKeyNameIndex == aKeyPressEvent.mKeyNameIndex &&
             mCodeNameIndex == aKeyPressEvent.mCodeNameIndex &&
             mKeyValue == aKeyPressEvent.mKeyValue &&
             mModifiers == aKeyPressEvent.mModifiers &&
             mAlternativeCharCodes == aKeyPressEvent.mAlternativeCharCodes;
    }

    CopyableTArray<AlternativeCharCode> mAlternativeCharCodes;
    uint32_t mKeyCode;
    uint32_t mCharCode;
    KeyNameIndex mKeyNameIndex;
    CodeNameIndex mCodeNameIndex;
    nsString mKeyValue;
    Modifiers mModifiers;
  };
  static Maybe<Data> sData;
  static int32_t sBrowserParentCount;
};
int32_t RequestingAccessKeyEventData::sBrowserParentCount = 0;
MOZ_RUNINIT Maybe<RequestingAccessKeyEventData::Data>
    RequestingAccessKeyEventData::sData;

namespace dom {

BrowserParent::LayerToBrowserParentTable*
    BrowserParent::sLayerToBrowserParentTable = nullptr;

NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(BrowserParent)
  NS_INTERFACE_MAP_ENTRY_CONCRETE(BrowserParent)
  NS_INTERFACE_MAP_ENTRY(nsIAuthPromptProvider)
  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
  NS_INTERFACE_MAP_ENTRY(nsIDOMEventListener)
  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDOMEventListener)
NS_INTERFACE_MAP_END

NS_IMPL_CYCLE_COLLECTION_CLASS(BrowserParent)

NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(BrowserParent)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFrameLoader)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowsingContext)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFrameElement)
  NS_IMPL_CYCLE_COLLECTION_UNLINK(mBrowserDOMWindow)
  tmp->UnlinkManager();
  NS_IMPL_CYCLE_COLLECTION_UNLINK_WEAK_REFERENCE
NS_IMPL_CYCLE_COLLECTION_UNLINK_END

NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(BrowserParent)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFrameLoader)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowsingContext)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFrameElement)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mBrowserDOMWindow)
  NS_IMPL_CYCLE_COLLECTION_TRAVERSE_RAWPTR(Manager())
NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END

NS_IMPL_CYCLE_COLLECTING_ADDREF(BrowserParent)
NS_IMPL_CYCLE_COLLECTING_RELEASE(BrowserParent)

BrowserParent::BrowserParent(ContentParent* aManager, const TabId& aTabId,
                             const TabContext& aContext,
                             CanonicalBrowsingContext* aBrowsingContext,
                             uint32_t aChromeFlags)
    : TabContext(aContext),
      mTabId(aTabId),
      mBrowsingContext(aBrowsingContext),
      mFrameElement(nullptr),
      mBrowserDOMWindow(nullptr),
      mFrameLoader(nullptr),
      mChromeFlags(aChromeFlags),
      mBrowserBridgeParent(nullptr),
      mBrowserHost(nullptr),
      mContentCache(*this),
      mRect(0, 0, 0, 0),
      mDimensions(0, 0),
      mDPI(0),
      mRounding(0),
      mDefaultScale(0),
      mUpdatedDimensions(false),
      mSizeMode(nsSizeMode_Normal),
      mCreatingWindow(false),
      mMarkedDestroying(false),
      mIsDestroyed(false),
      mRemoteTargetSetsCursor(false),
      mIsPreservingLayers(false),
      mRenderLayers(true),
      mPriorityHint(false),
      mHasLayers(false),
      mHasPresented(false),
      mIsReadyToHandleInputEvents(false),
      mIsMouseEnterIntoWidgetEventSuppressed(false),
      mLockedNativePointer(false),
      mShowingTooltip(false) {
  MOZ_ASSERT(aManager);

  // We access `Manager()` when updating priorities later in this constructor,
  // so need to initialize it before IPC does.
  SetManager(aManager);

  // Add a KeepAlive for this BrowserParent upon creation.
  mContentParentKeepAlive =
      aManager->TryAddKeepAlive(aBrowsingContext->BrowserId());

  RequestingAccessKeyEventData::OnBrowserParentCreated();

  // Make sure to compute our process priority if needed before the block of
  // code below. This makes sure the block below prioritizes our process if
  // needed.
  if (aBrowsingContext->IsTop()) {
    RecomputeProcessPriority();
  }

  // Reflect the BC tree's activeness state on this new BrowserParent. This
  // ensures that the process will be correctly prioritized based on the
  // BrowsingContext's current priority after a navigation.
  // If the BC is not active, we still call `BrowserPriorityChanged` to ensure
  // the priority is lowered if the BrowsingContext is inactive, but the process
  // still has FOREGROUND priority from when it was launched.
  ProcessPriorityManager::BrowserPriorityChanged(
      this, aBrowsingContext->Top()->IsPriorityActive());
}

BrowserParent::~BrowserParent() {
  RequestingAccessKeyEventData::OnBrowserParentDestroyed();
}

/* static */
BrowserParent* BrowserParent::GetFocused() { return sFocus; }

/* static */
BrowserParent* BrowserParent::GetLastMouseRemoteTarget() {
  return sLastMouseRemoteTarget;
}

/*static*/
BrowserParent* BrowserParent::GetFrom(nsFrameLoader* aFrameLoader) {
  if (!aFrameLoader) {
    return nullptr;
  }
  return aFrameLoader->GetBrowserParent();
}

/*static*/
BrowserParent* BrowserParent::GetFrom(PBrowserParent* aBrowserParent) {
  return static_cast<BrowserParent*>(aBrowserParent);
}

/*static*/
BrowserParent* BrowserParent::GetFrom(nsIContent* aContent) {
  RefPtr<nsFrameLoaderOwner> loaderOwner = do_QueryObject(aContent);
  if (!loaderOwner) {
    return nullptr;
  }
  RefPtr<nsFrameLoader> frameLoader = loaderOwner->GetFrameLoader();
  return GetFrom(frameLoader);
}

/* static */
BrowserParent* BrowserParent::GetBrowserParentFromLayersId(
    layers::LayersId aLayersId) {
  if (!sLayerToBrowserParentTable) {
    return nullptr;
  }
  return sLayerToBrowserParentTable->Get(uint64_t(aLayersId));
}

/*static*/
TabId BrowserParent::GetTabIdFrom(nsIDocShell* docShell) {
  nsCOMPtr<nsIBrowserChild> browserChild(BrowserChild::GetFrom(docShell));
  if (browserChild) {
    return static_cast<BrowserChild*>(browserChild.get())->GetTabId();
  }
  return TabId(0);
}

ContentParent* BrowserParent::Manager() const {
  return static_cast<ContentParent*>(PBrowserParent::Manager());
}

void BrowserParent::AddBrowserParentToTable(layers::LayersId aLayersId,
                                            BrowserParent* aBrowserParent) {
  if (!sLayerToBrowserParentTable) {
    sLayerToBrowserParentTable = new LayerToBrowserParentTable();
  }
  sLayerToBrowserParentTable->InsertOrUpdate(uint64_t(aLayersId),
                                             aBrowserParent);
}

void BrowserParent::RemoveBrowserParentFromTable(layers::LayersId aLayersId) {
  if (!sLayerToBrowserParentTable) {
    return;
  }
  sLayerToBrowserParentTable->Remove(uint64_t(aLayersId));
  if (sLayerToBrowserParentTable->Count() == 0) {
    delete sLayerToBrowserParentTable;
    sLayerToBrowserParentTable = nullptr;
  }
}

already_AddRefed<nsILoadContext> BrowserParent::GetLoadContext() {
  return do_AddRef(mBrowsingContext);
}

/**
 * Will return nullptr if there is no outer window available for the
 * document hosting the owner element of this BrowserParent. Also will return
 * nullptr if that outer window is in the process of closing.
 */
already_AddRefed<nsPIDOMWindowOuter> BrowserParent::GetParentWindowOuter() {
  nsCOMPtr<nsIContent> frame = GetOwnerElement();
  if (!frame) {
    return nullptr;
  }

  nsCOMPtr<nsPIDOMWindowOuter> parent = frame->OwnerDoc()->GetWindow();
  if (!parent || parent->Closed()) {
    return nullptr;
  }

  return parent.forget();
}

already_AddRefed<nsIWidget> BrowserParent::GetTopLevelWidget() {
  if (RefPtr<Element> element = mFrameElement) {
    if (PresShell* presShell = element->OwnerDoc()->GetPresShell()) {
      return do_AddRef(presShell->GetViewManager()->GetRootWidget());
    }
  }
  return nullptr;
}

already_AddRefed<nsIWidget> BrowserParent::GetTextInputHandlingWidget() const {
  if (!mFrameElement) {
    return nullptr;
  }
  PresShell* presShell = mFrameElement->OwnerDoc()->GetPresShell();
  if (!presShell) {
    return nullptr;
  }
  nsPresContext* presContext = presShell->GetPresContext();
  if (!presContext) {
    return nullptr;
  }
  nsCOMPtr<nsIWidget> widget = presContext->GetTextInputHandlingWidget();
  return widget.forget();
}

already_AddRefed<nsIWidget> BrowserParent::GetWidget() const {
  if (!mFrameElement) {
    return nullptr;
  }
  nsCOMPtr<nsIWidget> widget = nsContentUtils::WidgetForContent(mFrameElement);
  if (!widget) {
    widget = nsContentUtils::WidgetForDocument(mFrameElement->OwnerDoc());
  }
  return widget.forget();
}

already_AddRefed<nsIWidget> BrowserParent::GetDocWidget() const {
  if (!mFrameElement) {
    return nullptr;
  }
  return do_AddRef(
      nsContentUtils::WidgetForDocument(mFrameElement->OwnerDoc()));
}

nsIXULBrowserWindow* BrowserParent::GetXULBrowserWindow() {
  if (!mFrameElement) {
    return nullptr;
  }

  nsCOMPtr<nsIDocShell> docShell = mFrameElement->OwnerDoc()->GetDocShell();
  if (!docShell) {
    return nullptr;
  }

  nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
  docShell->GetTreeOwner(getter_AddRefs(treeOwner));
  if (!treeOwner) {
    return nullptr;
  }

  nsCOMPtr<nsIAppWindow> window = do_GetInterface(treeOwner);
  if (!window) {
    return nullptr;
  }

  nsCOMPtr<nsIXULBrowserWindow> xulBrowserWindow;
  window->GetXULBrowserWindow(getter_AddRefs(xulBrowserWindow));
  return xulBrowserWindow;
}

uint32_t BrowserParent::GetMaxTouchPoints(Element* aElement) {
  if (!aElement) {
    return 0;
  }

  if (StaticPrefs::dom_maxtouchpoints_testing_value() >= 0) {
    return StaticPrefs::dom_maxtouchpoints_testing_value();
  }

  nsIWidget* widget = nsContentUtils::WidgetForDocument(aElement->OwnerDoc());
  return widget ? widget->GetMaxTouchPoints() : 0;
}

a11y::DocAccessibleParent* BrowserParent::GetTopLevelDocAccessible() const {
#ifdef ACCESSIBILITY
  // XXX Consider managing non top level PDocAccessibles with their parent
  // document accessible.
  const ManagedContainer<PDocAccessibleParent>& docs =
      ManagedPDocAccessibleParent();
  for (auto* key : docs) {
    auto* doc = static_cast<a11y::DocAccessibleParent*>(key);
    // We want the document for this BrowserParent even if it's for an
    // embedded out-of-process iframe. Therefore, we use
    // IsTopLevelInContentProcess. In contrast, using IsToplevel would only
    // include documents that aren't embedded; e.g. tab documents.
    if (doc->IsTopLevelInContentProcess() && !doc->IsShutdown()) {
      return doc;
    }
  }
#endif
  return nullptr;
}

LayersId BrowserParent::GetLayersId() const {
  if (!mRemoteLayerTreeOwner.IsInitialized()) {
    return LayersId{};
  }
  return mRemoteLayerTreeOwner.GetLayersId();
}

BrowserBridgeParent* BrowserParent::GetBrowserBridgeParent() const {
  return mBrowserBridgeParent;
}

BrowserHost* BrowserParent::GetBrowserHost() const { return mBrowserHost; }

ParentShowInfo BrowserParent::GetShowInfo() {
  TryCacheDPIAndScale();
  if (mFrameElement) {
    nsAutoString name;
    mFrameElement->GetAttr(nsGkAtoms::name, name);
    bool isTransparent =
        nsContentUtils::IsChromeDoc(mFrameElement->OwnerDoc()) &&
        mFrameElement->HasAttr(nsGkAtoms::transparent);
    return ParentShowInfo(name, false, isTransparent, mDPI, mRounding,
                          mDefaultScale.scale);
  }

  return ParentShowInfo(u""_ns, false, false, mDPI, mRounding,
                        mDefaultScale.scale);
}

already_AddRefed<nsIPrincipal> BrowserParent::GetContentPrincipal() const {
  nsCOMPtr<nsIBrowser> browser =
      mFrameElement ? mFrameElement->AsBrowser() : nullptr;
  NS_ENSURE_TRUE(browser, nullptr);

  RefPtr<nsIPrincipal> principal;

  nsresult rv;
  rv = browser->GetContentPrincipal(getter_AddRefs(principal));
  NS_ENSURE_SUCCESS(rv, nullptr);

  return principal.forget();
}

void BrowserParent::SetOwnerElement(Element* aElement) {
  // If we held previous content then unregister for its events.
  RemoveWindowListeners();

  // If we change top-level documents then we need to change our
  // registration with them.
  RefPtr<nsPIWindowRoot> curTopLevelWin, newTopLevelWin;
  if (mFrameElement) {
    curTopLevelWin = nsContentUtils::GetWindowRoot(mFrameElement->OwnerDoc());
  }
  if (aElement) {
    newTopLevelWin = nsContentUtils::GetWindowRoot(aElement->OwnerDoc());
  }
  bool isSameTopLevelWin = curTopLevelWin == newTopLevelWin;
  if (mBrowserHost && curTopLevelWin && !isSameTopLevelWin) {
    curTopLevelWin->RemoveBrowser(mBrowserHost);
  }

  // Update to the new content, and register to listen for events from it.
  mFrameElement = aElement;

  if (mBrowserHost && newTopLevelWin && !isSameTopLevelWin) {
    newTopLevelWin->AddBrowser(mBrowserHost);
  }

#if defined(XP_WIN) && defined(ACCESSIBILITY)
  if (!mIsDestroyed) {
    uintptr_t newWindowHandle = 0;
    if (nsCOMPtr<nsIWidget> widget = GetWidget()) {
      newWindowHandle =
          reinterpret_cast<uintptr_t>(widget->GetNativeData(NS_NATIVE_WINDOW));
    }
    Unused << SendUpdateNativeWindowHandle(newWindowHandle);
    a11y::DocAccessibleParent* doc = GetTopLevelDocAccessible();
    if (doc) {
      HWND hWnd = reinterpret_cast<HWND>(doc->GetEmulatedWindowHandle());
      if (hWnd) {
        HWND parentHwnd = reinterpret_cast<HWND>(newWindowHandle);
        if (parentHwnd != ::GetParent(hWnd)) {
          ::SetParent(hWnd, parentHwnd);
        }
      }
    }
  }
#endif

  AddWindowListeners();

  // The DPI depends on our frame element's widget, so invalidate now in case
  // we've tried to cache it already.
  mDPI = -1;
  TryCacheDPIAndScale();

  if (mRemoteLayerTreeOwner.IsInitialized()) {
    mRemoteLayerTreeOwner.OwnerContentChanged();
  }

  // Set our BrowsingContext's embedder if we're not embedded within a
  // BrowserBridgeParent.
  if (!GetBrowserBridgeParent() && mBrowsingContext && mFrameElement) {
    mBrowsingContext->SetEmbedderElement(mFrameElement);
  }

  UpdateVsyncParentVsyncDispatcher();

  VisitChildren([aElement](BrowserBridgeParent* aBrowser) {
    if (auto* browserParent = aBrowser->GetBrowserParent()) {
      browserParent->SetOwnerElement(aElement);
    }
  });
}

void BrowserParent::CacheFrameLoader(nsFrameLoader* aFrameLoader) {
  mFrameLoader = aFrameLoader;
}

void BrowserParent::AddWindowListeners() {
  if (mFrameElement) {
    if (nsCOMPtr<nsPIDOMWindowOuter> window =
            mFrameElement->OwnerDoc()->GetWindow()) {
      nsCOMPtr<EventTarget> eventTarget = window->GetTopWindowRoot();
      if (eventTarget) {
        eventTarget->AddEventListener(u"MozUpdateWindowPos"_ns, this, false,
                                      false);
        eventTarget->AddEventListener(u"fullscreenchange"_ns, this, false,
                                      false);
      }
    }
  }
}

void BrowserParent::RemoveWindowListeners() {
  if (mFrameElement && mFrameElement->OwnerDoc()->GetWindow()) {
    nsCOMPtr<nsPIDOMWindowOuter> window =
        mFrameElement->OwnerDoc()->GetWindow();
    nsCOMPtr<EventTarget> eventTarget = window->GetTopWindowRoot();
    if (eventTarget) {
      eventTarget->RemoveEventListener(u"MozUpdateWindowPos"_ns, this, false);
      eventTarget->RemoveEventListener(u"fullscreenchange"_ns, this, false);
    }
  }
}

void BrowserParent::Deactivated() {
  if (mShowingTooltip) {
    // Reuse the normal tooltip hiding method.
    mozilla::Unused << RecvHideTooltip();
  }
  UnlockNativePointer();
  UnsetTopLevelWebFocus(this);
  UnsetLastMouseRemoteTarget(this);
  PointerLockManager::ReleaseLockedRemoteTarget(this);
  PointerEventHandler::ReleasePointerCaptureRemoteTarget(this);
  PresShell::ReleaseCapturingRemoteTarget(this);
  ProcessPriorityManager::BrowserPriorityChanged(this, /* aPriority = */ false);
}

void BrowserParent::Destroy() {
  // Aggressively release the window to avoid leaking the world in shutdown
  // corner cases.
  mBrowserDOMWindow = nullptr;

  if (mIsDestroyed) {
    return;
  }

  Deactivated();

  RemoveWindowListeners();

#ifdef ACCESSIBILITY
  if (a11y::DocAccessibleParent* tabDoc = GetTopLevelDocAccessible()) {
#  if defined(ANDROID)
    MonitorAutoLock mal(nsAccessibilityService::GetAndroidMonitor());
#  endif
    tabDoc->Destroy();
  }
#endif

  // If this fails, it's most likely due to a content-process crash, and
  // auto-cleanup will kick in.  Otherwise, the child side will destroy itself
  // and send back __delete__().
  (void)SendDestroy();
  mIsDestroyed = true;

#if !defined(MOZ_WIDGET_ANDROID)
  // We're beginning to destroy this BrowserParent. Immediately drop the
  // keepalive. This can start the shutdown timer, however the ShutDown message
  // will wait for the BrowserParent to be fully destroyed.
  //
  // NOTE: We intentionally skip this step on Android, keeping the KeepAlive
  // active until the BrowserParent is fully destroyed:
  // 1. Android has a fixed upper bound on the number of content processes, so
  //    we prefer to re-use them whenever possible (as opposed to letting an
  //    old process wind down while we launch a new one). This restriction will
  //    be relaxed after bug 1565196.
  // 2. GeckoView always hard-kills content processes (and if it does not,
  //    Android itself will), so we don't concern ourselves with the ForceKill
  //    timer either.
  mContentParentKeepAlive = nullptr;
#endif

  // This `AddKeepAlive` will be cleared if `mMarkedDestroying` is set in
  // `ActorDestroy`. Out of caution, we don't add the `KeepAlive` if our IPC
  // actor has somehow already been destroyed, as that would mean `ActorDestroy`
  // won't be called.
  if (CanRecv()) {
    mBrowsingContext->Group()->AddKeepAlive();
  }

  mMarkedDestroying = true;
}

mozilla::ipc::IPCResult BrowserParent::RecvDidUnsuppressPainting() {
  if (!mFrameElement) {
    return IPC_OK();
  }
  nsSubDocumentFrame* subdocFrame =
      do_QueryFrame(mFrameElement->GetPrimaryFrame());
  if (subdocFrame && subdocFrame->HasRetainedPaintData()) {
    subdocFrame->ClearRetainedPaintData();
  }
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvEnsureLayersConnected(
    CompositorOptions* aCompositorOptions) {
  if (mRemoteLayerTreeOwner.IsInitialized()) {
    mRemoteLayerTreeOwner.EnsureLayersConnected(aCompositorOptions);
  }
  return IPC_OK();
}

void BrowserParent::ActorDestroy(ActorDestroyReason why) {
  // Need to close undeleted ContentPermissionRequestParents before tab is
  // closed.
  // FIXME: Why is PContentPermissionRequest not managed by PBrowser?
  nsTArray<PContentPermissionRequestParent*> parentArray =
      nsContentPermissionUtils::GetContentPermissionRequestParentById(mTabId);
  for (auto& permissionRequestParent : parentArray) {
    Unused << PContentPermissionRequestParent::Send__delete__(
        permissionRequestParent);
  }

  // Ensure the ContentParentKeepAlive has been cleared when the actor is
  // destroyed, and re-check if it's time to send the ShutDown message.
  mContentParentKeepAlive = nullptr;
  Manager()->MaybeBeginShutDown();

  ContentProcessManager* cpm = ContentProcessManager::GetSingleton();
  if (cpm) {
    cpm->UnregisterRemoteFrame(mTabId);
  }

  if (mRemoteLayerTreeOwner.IsInitialized()) {
    auto layersId = mRemoteLayerTreeOwner.GetLayersId();
    if (mFrameElement) {
      nsSubDocumentFrame* f = do_QueryFrame(mFrameElement->GetPrimaryFrame());
      if (f && f->HasRetainedPaintData() &&
          f->GetRemotePaintData().mLayersId == layersId) {
        f->ClearRetainedPaintData();
      }
    }

    // It's important to unmap layers after the remote browser has been
    // destroyed, otherwise it may still send messages to the compositor which
    // will reject them, causing assertions.
    RemoveBrowserParentFromTable(layersId);
    mRemoteLayerTreeOwner.Destroy();
  }

  // Even though BrowserParent::Destroy calls this, we need to do it here too in
  // case of a crash.
  Deactivated();

  if (why == AbnormalShutdown) {
    // dom_reporting_header must also be enabled for the report to be sent.
    if (StaticPrefs::dom_reporting_crash_enabled()) {
      nsCOMPtr<nsIPrincipal> principal = GetContentPrincipal();

      if (principal) {
        nsAutoCString crash_reason;
        CrashReporter::GetAnnotation(OtherPid(),
                                     CrashReporter::Annotation::MozCrashReason,
                                     crash_reason);
        // FIXME(arenevier): Find a less fragile way to identify that a crash
        // was caused by OOM
        bool is_oom = false;
        if (crash_reason == "OOM" || crash_reason == "OOM!" ||
            StringBeginsWith(crash_reason, "[unhandlable oom]"_ns) ||
            StringBeginsWith(crash_reason, "Unhandlable OOM"_ns)) {
          is_oom = true;
        }

        CrashReport::Deliver(principal, is_oom);
      }
    }
  }

  // If we were shutting down normally, we held a reference to our
  // BrowsingContextGroup in `BrowserParent::Destroy`. Clear that reference
  // here.
  if (mMarkedDestroying) {
    mBrowsingContext->Group()->RemoveKeepAlive();
  }

  // Tell our embedder that the tab is now going away unless we're an
  // out-of-process iframe.
  RefPtr<nsFrameLoader> frameLoader = GetFrameLoader(true);
  if (frameLoader) {
    if (mBrowsingContext->IsTop()) {
      // If this is a top-level BrowsingContext, tell the frameloader it's time
      // to go away. Otherwise, this is a subframe crash, and we can keep the
      // frameloader around.
      frameLoader->DestroyComplete();
    }

    // If this was a crash, tell our nsFrameLoader to fire crash events.
    if (why == AbnormalShutdown) {
      frameLoader->MaybeNotifyCrashed(mBrowsingContext, Manager()->ChildID(),
                                      GetIPCChannel());
    } else if (why == ManagedEndpointDropped) {
      // If we instead failed due to a constructor error, don't include process
      // information, as the process did not crash.
      frameLoader->MaybeNotifyCrashed(mBrowsingContext, ContentParentId{},
                                      nullptr);
    }
  }

  mFrameLoader = nullptr;

  // If we were destroyed due to our ManagedEndpoints being dropped, make a
  // point of showing the subframe crashed UI. We don't fire the full
  // `MaybeNotifyCrashed` codepath, as the entire process hasn't crashed on us,
  // and it may confuse the frontend.
  mBrowsingContext->BrowserParentDestroyed(
      this, why == AbnormalShutdown || why == ManagedEndpointDropped);
}

mozilla::ipc::IPCResult BrowserParent::RecvMoveFocus(
    const bool& aForward, const bool& aForDocumentNavigation) {
  LOGBROWSERFOCUS(("RecvMoveFocus %p, aForward: %d, aForDocumentNavigation: %d",
                   this, aForward, aForDocumentNavigation));
  BrowserBridgeParent* bridgeParent = GetBrowserBridgeParent();
  if (bridgeParent) {
    mozilla::Unused << bridgeParent->SendMoveFocus(aForward,
                                                   aForDocumentNavigation);
    return IPC_OK();
  }

  RefPtr<nsFocusManager> fm = nsFocusManager::GetFocusManager();
  if (fm) {
    RefPtr<Element> dummy;

    uint32_t type =
        aForward
            ? (aForDocumentNavigation
                   ? static_cast<uint32_t>(
                         nsIFocusManager::MOVEFOCUS_FORWARDDOC)
                   : static_cast<uint32_t>(nsIFocusManager::MOVEFOCUS_FORWARD))
            : (aForDocumentNavigation
                   ? static_cast<uint32_t>(
                         nsIFocusManager::MOVEFOCUS_BACKWARDDOC)
                   : static_cast<uint32_t>(
                         nsIFocusManager::MOVEFOCUS_BACKWARD));
    fm->MoveFocus(nullptr, mFrameElement, type, nsIFocusManager::FLAG_BYKEY,
                  getter_AddRefs(dummy));
  }
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvDropLinks(
    nsTArray<nsString>&& aLinks) {
  nsCOMPtr<nsIBrowser> browser =
      mFrameElement ? mFrameElement->AsBrowser() : nullptr;
  if (browser) {
    // Verify that links have not been modified by the child. If links have
    // not been modified then it's safe to load those links using the
    // SystemPrincipal. If they have been modified by web content, then
    // we use a NullPrincipal which still allows to load web links.
    bool loadUsingSystemPrincipal = true;
    if (aLinks.Length() != mVerifyDropLinks.Length()) {
      loadUsingSystemPrincipal = false;
    }
    for (uint32_t i = 0; i < aLinks.Length(); i++) {
      if (loadUsingSystemPrincipal) {
        if (!aLinks[i].Equals(mVerifyDropLinks[i])) {
          loadUsingSystemPrincipal = false;
        }
      }
    }
    mVerifyDropLinks.Clear();
    nsCOMPtr<nsIPrincipal> triggeringPrincipal;
    if (loadUsingSystemPrincipal) {
      triggeringPrincipal = nsContentUtils::GetSystemPrincipal();
    } else {
      triggeringPrincipal = NullPrincipal::CreateWithoutOriginAttributes();
    }
    browser->DropLinks(aLinks, triggeringPrincipal);
  }
  return IPC_OK();
}

bool BrowserParent::SendLoadRemoteScript(const nsAString& aURL,
                                         const bool& aRunInGlobalScope) {
  if (mCreatingWindow) {
    mDelayedFrameScripts.AppendElement(
        FrameScriptInfo(nsString(aURL), aRunInGlobalScope));
    return true;
  }

  MOZ_ASSERT(mDelayedFrameScripts.IsEmpty());
  return PBrowserParent::SendLoadRemoteScript(aURL, aRunInGlobalScope);
}

void BrowserParent::LoadURL(nsDocShellLoadState* aLoadState) {
  MOZ_ASSERT(aLoadState);
  MOZ_ASSERT(aLoadState->URI());
  if (mIsDestroyed) {
    return;
  }

  if (mCreatingWindow) {
    // Don't send the message if the child wants to load its own URL.
    return;
  }

  Unused << SendLoadURL(WrapNotNull(aLoadState), GetShowInfo());
}

void BrowserParent::ResumeLoad(uint64_t aPendingSwitchID) {
  MOZ_ASSERT(aPendingSwitchID != 0);

  if (NS_WARN_IF(mIsDestroyed)) {
    return;
  }

  Unused << SendResumeLoad(aPendingSwitchID, GetShowInfo());
}

void BrowserParent::InitRendering() {
  if (mRemoteLayerTreeOwner.IsInitialized()) {
    return;
  }
  mRemoteLayerTreeOwner.Initialize(this);

  layers::LayersId layersId = mRemoteLayerTreeOwner.GetLayersId();
  AddBrowserParentToTable(layersId, this);

  RefPtr<nsFrameLoader> frameLoader = GetFrameLoader();
  if (frameLoader) {
    nsIFrame* frame = frameLoader->GetPrimaryFrameOfOwningContent();
    if (frame) {
      frame->InvalidateFrame();
    }
  }

  TextureFactoryIdentifier textureFactoryIdentifier;
  mRemoteLayerTreeOwner.GetTextureFactoryIdentifier(&textureFactoryIdentifier);
  Unused << SendInitRendering(textureFactoryIdentifier, layersId,
                              mRemoteLayerTreeOwner.GetCompositorOptions(),
                              mRemoteLayerTreeOwner.IsLayersConnected());

  RefPtr<nsIWidget> widget = GetTopLevelWidget();
  if (widget) {
    Unused << SendSafeAreaInsetsChanged(widget->GetSafeAreaInsets());
  }

#if defined(MOZ_WIDGET_ANDROID)
  MOZ_ASSERT(widget);

  if (GetBrowsingContext()->IsTopContent()) {
    Unused << SendDynamicToolbarMaxHeightChanged(
        widget->GetDynamicToolbarMaxHeight());
  }
#endif
}

bool BrowserParent::AttachWindowRenderer() {
  return mRemoteLayerTreeOwner.AttachWindowRenderer();
}

void BrowserParent::MaybeShowFrame() {
  RefPtr<nsFrameLoader> frameLoader = GetFrameLoader();
  if (!frameLoader) {
    return;
  }
  frameLoader->MaybeShowFrame();
}

bool BrowserParent::Show(const OwnerShowInfo& aOwnerInfo) {
  mDimensions = aOwnerInfo.size();
  if (mIsDestroyed) {
    return false;
  }

  MOZ_ASSERT(mRemoteLayerTreeOwner.IsInitialized());
  if (!mRemoteLayerTreeOwner.AttachWindowRenderer()) {
    return false;
  }

  mSizeMode = aOwnerInfo.sizeMode();
  Unused << SendShow(GetShowInfo(), aOwnerInfo);
  return true;
}

mozilla::ipc::IPCResult BrowserParent::RecvSetDimensions(
    mozilla::DimensionRequest aRequest, const double& aScale) {
  NS_ENSURE_TRUE(mFrameElement, IPC_OK());
  nsCOMPtr<nsIDocShell> docShell = mFrameElement->OwnerDoc()->GetDocShell();
  NS_ENSURE_TRUE(docShell, IPC_OK());
  nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
  docShell->GetTreeOwner(getter_AddRefs(treeOwner));
  nsCOMPtr<nsIBaseWindow> treeOwnerAsWin = do_QueryInterface(treeOwner);
  NS_ENSURE_TRUE(treeOwnerAsWin, IPC_OK());

  // `BrowserChild` only sends the values to actually be changed, see more
  // details in `BrowserChild::SetDimensions()`.
  // Note that `BrowserChild::SetDimensions()` may be called before receiving
  // our `SendUIResolutionChanged()` call.  Therefore, if given each coordinate
  // shouldn't be ignored, we need to recompute it if DPI has been changed.
  // And also note that don't use `mDefaultScale.scale` here since it may be
  // different from the result of `GetWidgetCSSToDeviceScale()`.
  // NOTE(emilio): We use GetWidgetCSSToDeviceScale() because the old scale is a
  // widget scale, and we only use the current scale to scale up/down the
  // relevant values.

  CSSToLayoutDeviceScale oldScale((float)aScale);
  CSSToLayoutDeviceScale currentScale(
      (float)treeOwnerAsWin->GetWidgetCSSToDeviceScale());

  if (oldScale != currentScale) {
    auto rescaleFunc = [&oldScale, ¤tScale](LayoutDeviceIntCoord& aVal) {
      aVal = (LayoutDeviceCoord(aVal) / oldScale * currentScale).Rounded();
    };
    aRequest.mX.apply(rescaleFunc);
    aRequest.mY.apply(rescaleFunc);
    aRequest.mWidth.apply(rescaleFunc);
    aRequest.mHeight.apply(rescaleFunc);
  }

  // treeOwner is the chrome tree owner, but we wan't the content tree owner.
  nsCOMPtr<nsIWebBrowserChrome> webBrowserChrome = do_GetInterface(treeOwner);
  NS_ENSURE_TRUE(webBrowserChrome, IPC_OK());
  webBrowserChrome->SetDimensions(std::move(aRequest));
  return IPC_OK();
}

nsresult BrowserParent::UpdatePosition() {
  RefPtr<nsFrameLoader> frameLoader = GetFrameLoader();
  if (!frameLoader) {
    return NS_OK;
  }
  LayoutDeviceIntRect windowDims;
  NS_ENSURE_SUCCESS(frameLoader->GetWindowDimensions(windowDims),
                    NS_ERROR_FAILURE);
  // Avoid updating sizes here.
  windowDims.SizeTo(mRect.Size());
  UpdateDimensions(windowDims, mDimensions);
  return NS_OK;
}

void BrowserParent::NotifyPositionUpdatedForContentsInPopup() {
  if (CanonicalBrowsingContext* bc = GetBrowsingContext()) {
    bc->PreOrderWalk([](BrowsingContext* aContext) {
      if (WindowGlobalParent* windowGlobalParent =
              aContext->Canonical()->GetCurrentWindowGlobal()) {
        if (RefPtr<BrowserParent> browserParent =
                windowGlobalParent->GetBrowserParent()) {
          browserParent->UpdatePosition();
        }
      }
    });
  }
}

void BrowserParent::UpdateDimensions(const LayoutDeviceIntRect& rect,
                                     const LayoutDeviceIntSize& size) {
  if (mIsDestroyed) {
    return;
  }
  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    NS_WARNING("No widget found in BrowserParent::UpdateDimensions");
    return;
  }

  LayoutDeviceIntPoint clientOffset = GetClientOffset();
  LayoutDeviceIntPoint chromeOffset = !GetBrowserBridgeParent()
                                          ? -GetChildProcessOffset()
                                          : LayoutDeviceIntPoint();

  if (!mUpdatedDimensions || mDimensions != size || !mRect.IsEqualEdges(rect) ||
      clientOffset != mClientOffset || chromeOffset != mChromeOffset) {
    mUpdatedDimensions = true;
    mRect = rect;
    mDimensions = size;
    mClientOffset = clientOffset;
    mChromeOffset = chromeOffset;

    Unused << SendUpdateDimensions(GetDimensionInfo());
    UpdateNativePointerLockCenter(widget);
  }
}

DimensionInfo BrowserParent::GetDimensionInfo() {
  CSSRect unscaledRect = mRect / mDefaultScale;
  CSSSize unscaledSize = mDimensions / mDefaultScale;
  return DimensionInfo(unscaledRect, unscaledSize, mClientOffset,
                       mChromeOffset);
}

void BrowserParent::UpdateNativePointerLockCenter(nsIWidget* aWidget) {
  if (!mLockedNativePointer) {
    return;
  }
  aWidget->SetNativePointerLockCenter(
      LayoutDeviceIntRect(mChromeOffset, mDimensions).Center());
}

void BrowserParent::SizeModeChanged(const nsSizeMode& aSizeMode) {
  if (!mIsDestroyed && aSizeMode != mSizeMode) {
    mSizeMode = aSizeMode;
    Unused << SendSizeModeChanged(aSizeMode);
  }
}

#if defined(MOZ_WIDGET_ANDROID)
void BrowserParent::DynamicToolbarMaxHeightChanged(ScreenIntCoord aHeight) {
  if (!mIsDestroyed) {
    Unused << SendDynamicToolbarMaxHeightChanged(aHeight);
  }
}

void BrowserParent::DynamicToolbarOffsetChanged(ScreenIntCoord aOffset) {
  if (!mIsDestroyed) {
    Unused << SendDynamicToolbarOffsetChanged(aOffset);
  }
}

void BrowserParent::KeyboardHeightChanged(ScreenIntCoord aHeight) {
  if (!mIsDestroyed) {
    Unused << SendKeyboardHeightChanged(aHeight);
  }
}
#endif

void BrowserParent::HandleAccessKey(const WidgetKeyboardEvent& aEvent,
                                    nsTArray<uint32_t>& aCharCodes) {
  if (!mIsDestroyed) {
    // Note that we don't need to mark aEvent is posted to a remote process
    // because the event may be dispatched to it as normal keyboard event.
    // Therefore, we should use local copy to send it.
    WidgetKeyboardEvent localEvent(aEvent);
    RequestingAccessKeyEventData::Set(localEvent);
    Unused << SendHandleAccessKey(localEvent, aCharCodes);
  }
}

void BrowserParent::Activate(uint64_t aActionId) {
  LOGBROWSERFOCUS(("Activate %p actionid: %" PRIu64, this, aActionId));
  if (!mIsDestroyed) {
    SetTopLevelWebFocus(this);  // Intentionally inside "if"
    Unused << SendActivate(aActionId);
  }
}

void BrowserParent::Deactivate(bool aWindowLowering, uint64_t aActionId) {
  LOGBROWSERFOCUS(("Deactivate %p actionid: %" PRIu64, this, aActionId));
  if (!aWindowLowering) {
    UnsetTopLevelWebFocus(this);  // Intentionally outside the next "if"
  }
  if (!mIsDestroyed) {
    Unused << SendDeactivate(aActionId);
  }
}

#ifdef ACCESSIBILITY
a11y::PDocAccessibleParent* BrowserParent::AllocPDocAccessibleParent(
    PDocAccessibleParent* aParent, const uint64_t&,
    const MaybeDiscardedBrowsingContext&) {
  // Reference freed in DeallocPDocAccessibleParent.
  return a11y::DocAccessibleParent::New().take();
}

bool BrowserParent::DeallocPDocAccessibleParent(PDocAccessibleParent* aParent) {
  // Free reference from AllocPDocAccessibleParent.
  static_cast<a11y::DocAccessibleParent*>(aParent)->Release();
  return true;
}

mozilla::ipc::IPCResult BrowserParent::RecvPDocAccessibleConstructor(
    PDocAccessibleParent* aDoc, PDocAccessibleParent* aParentDoc,
    const uint64_t& aParentID,
    const MaybeDiscardedBrowsingContext& aBrowsingContext) {
#  if defined(ANDROID)
  MonitorAutoLock mal(nsAccessibilityService::GetAndroidMonitor());
#  endif
  auto doc = static_cast<a11y::DocAccessibleParent*>(aDoc);

  // If this tab is already shutting down just mark the new actor as shutdown
  // and ignore it.  When the tab actor is destroyed it will be too.
  if (mIsDestroyed) {
    doc->MarkAsShutdown();
    return IPC_OK();
  }

  if (aParentDoc) {
    // Iframe document rendered in the same process as its embedder.
    // A document should never directly be the parent of another document.
    // There should always be an outer doc accessible child of the outer
    // document containing the child.
    MOZ_ASSERT(aParentID);
    if (!aParentID) {
      return IPC_FAIL_NO_REASON(this);
    }

    auto parentDoc = static_cast<a11y::DocAccessibleParent*>(aParentDoc);
    if (parentDoc->IsShutdown()) {
      // This can happen if parentDoc is an OOP iframe, but its embedder has
      // been destroyed. (DocAccessibleParent::Destroy destroys any child
      // documents.) The OOP iframe (and anything it embeds) will die soon
      // anyway, so mark this document as shutdown and ignore it.
      doc->MarkAsShutdown();
      return IPC_OK();
    }

    if (aBrowsingContext) {
      doc->SetBrowsingContext(aBrowsingContext.get_canonical());
    }

    mozilla::ipc::IPCResult added = parentDoc->AddChildDoc(doc, aParentID);
    if (!added) {
#  ifdef DEBUG
      return added;
#  else
      return IPC_OK();
#  endif
    }

#  ifdef XP_WIN
    if (a11y::nsWinUtils::IsWindowEmulationStarted()) {
      doc->SetEmulatedWindowHandle(parentDoc->GetEmulatedWindowHandle());
    }
#  endif

    return IPC_OK();
  }

  if (aBrowsingContext) {
    doc->SetBrowsingContext(aBrowsingContext.get_canonical());
  }

  if (auto* bridge = GetBrowserBridgeParent()) {
    // Iframe document rendered in a different process to its embedder.
    // In this case, we don't get aParentDoc and aParentID.
    MOZ_ASSERT(!aParentDoc && !aParentID);
    doc->SetTopLevelInContentProcess();
    a11y::ProxyCreated(doc);
    // It's possible the embedder accessible hasn't been set yet; e.g.
    // a hidden iframe. In that case, embedderDoc will be null and this will
    // be handled when the embedder is set.
    if (a11y::DocAccessibleParent* embedderDoc =
            bridge->GetEmbedderAccessibleDoc()) {
      mozilla::ipc::IPCResult added = embedderDoc->AddChildDoc(bridge);
      if (!added) {
#  ifdef DEBUG
        return added;
#  else
        return IPC_OK();
#  endif
      }
    }
    return IPC_OK();
  } else {
    // null aParentDoc means this document is at the top level in the child
    // process.  That means it makes no sense to get an id for an accessible
    // that is its parent.
    MOZ_ASSERT(!aParentID);
    if (aParentID) {
      return IPC_FAIL_NO_REASON(this);
    }

    if (auto* prevTopLevel = GetTopLevelDocAccessible()) {
      // Sometimes, we can get a new top level DocAccessibleParent before the
      // old one gets destroyed. The old one will die pretty shortly anyway,
      // so just destroy it now. If we don't do this, GetTopLevelDocAccessible()
      // might return the wrong document for a short while.
      prevTopLevel->Destroy();
    }
    doc->SetTopLevel();
    a11y::DocManager::RemoteDocAdded(doc);
#  ifdef XP_WIN
    doc->MaybeInitWindowEmulation();
#  endif
  }
  return IPC_OK();
}
#endif

already_AddRefed<PFilePickerParent> BrowserParent::AllocPFilePickerParent(
    const nsString& aTitle, const nsIFilePicker::Mode& aMode,
    const MaybeDiscarded<BrowsingContext>& aBrowsingContext) {
  RefPtr<CanonicalBrowsingContext> browsingContext =
      [&]() -> CanonicalBrowsingContext* {
    if (aBrowsingContext.IsNullOrDiscarded()) {
      return nullptr;
    }
    if (!aBrowsingContext.get_canonical()->IsOwnedByProcess(
            Manager()->ChildID())) {
      return nullptr;
    }
    return aBrowsingContext.get_canonical();
  }();
  return MakeAndAddRef<FilePickerParent>(aTitle, aMode, browsingContext);
}

already_AddRefed<PSessionStoreParent>
BrowserParent::AllocPSessionStoreParent() {
  RefPtr<BrowserSessionStore> sessionStore =
      BrowserSessionStore::GetOrCreate(mBrowsingContext->Top());
  if (!sessionStore) {
    return nullptr;
  }

  return do_AddRef(new SessionStoreParent(mBrowsingContext, sessionStore));
}

IPCResult BrowserParent::RecvNewWindowGlobal(
    ManagedEndpoint<PWindowGlobalParent>&& aEndpoint,
    const WindowGlobalInit& aInit) {
  RefPtr<CanonicalBrowsingContext> browsingContext =
      CanonicalBrowsingContext::Get(aInit.context().mBrowsingContextId);
  if (!browsingContext) {
    return IPC_FAIL(this, "Cannot create for missing BrowsingContext");
  }
  if (!aInit.principal()) {
    return IPC_FAIL(this, "Cannot create without valid principal");
  }

  // Ensure we never load a document with a content principal in
  // the wrong type of webIsolated process
  EnumSet<ContentParent::ValidatePrincipalOptions> validationOptions = {};
  nsCOMPtr<nsIURI> docURI = aInit.documentURI();
  if (docURI->SchemeIs("blob") || docURI->SchemeIs("chrome")) {
    // XXXckerschb TODO - Do not use SystemPrincipal for:
    // Bug 1699385: Remove allowSystem for blobs
    // Bug 1698087: chrome://devtools/content/shared/webextension-fallback.html
    // chrome reftests, e.g.
    //   * chrome://reftest/content/writing-mode/ua-style-sheet-button-1a-ref.html
    //   * chrome://reftest/content/xul-document-load/test003.xhtml
    //   * chrome://reftest/content/forms/input/text/centering-1.xhtml
    validationOptions = {ContentParent::ValidatePrincipalOptions::AllowSystem};
  }

  // Some reftests have frames inside their chrome URIs and those load
  // about:blank:
  if (xpc::IsInAutomation() && docURI->SchemeIs("about")) {
    WindowGlobalParent* wgp = browsingContext->GetParentWindowContext();
    nsAutoCString spec;
    NS_ENSURE_SUCCESS(docURI->GetSpec(spec),
                      IPC_FAIL(this, "Should have spec for about: URI"));
    if (spec.Equals("about:blank") && wgp &&
        wgp->DocumentPrincipal()->IsSystemPrincipal()) {
      validationOptions = {
          ContentParent::ValidatePrincipalOptions::AllowSystem};
    }
  }

  if (!Manager()->ValidatePrincipal(aInit.principal(), validationOptions)) {
    ContentParent::LogAndAssertFailedPrincipalValidationInfo(aInit.principal(),
                                                             __func__);
  }

  // Construct our new WindowGlobalParent, bind, and initialize it.
  RefPtr<WindowGlobalParent> wgp =
      WindowGlobalParent::CreateDisconnected(aInit);
  BindPWindowGlobalEndpoint(std::move(aEndpoint), wgp);
  wgp->Init();
  return IPC_OK();
}

already_AddRefed<PVsyncParent> BrowserParent::AllocPVsyncParent() {
  return MakeAndAddRef<VsyncParent>();
}

IPCResult BrowserParent::RecvPVsyncConstructor(PVsyncParent* aActor) {
  UpdateVsyncParentVsyncDispatcher();
  return IPC_OK();
}

void BrowserParent::UpdateVsyncParentVsyncDispatcher() {
  VsyncParent* actor = static_cast<VsyncParent*>(
      LoneManagedOrNullAsserts(ManagedPVsyncParent()));
  if (!actor) {
    return;
  }

  if (nsCOMPtr<nsIWidget> widget = GetWidget()) {
    RefPtr<VsyncDispatcher> vsyncDispatcher = widget->GetVsyncDispatcher();
    if (!vsyncDispatcher) {
      vsyncDispatcher = gfxPlatform::GetPlatform()->GetGlobalVsyncDispatcher();
    }
    actor->UpdateVsyncDispatcher(vsyncDispatcher);
  }
}

void BrowserParent::MouseEnterIntoWidget() {
  if (nsCOMPtr<nsIWidget> widget = GetWidget()) {
    // When we mouseenter the remote target, the remote target's cursor should
    // become the current cursor.  When we mouseexit, we stop.
    mRemoteTargetSetsCursor = true;
    if (!EventStateManager::CursorSettingManagerHasLockedCursor()) {
      widget->SetCursor(mCursor);
      EventStateManager::ClearCursorSettingManager();
    }
  }

  // Mark that we have missed a mouse enter event, so that
  // the next mouse event will create a replacement mouse
  // enter event and send it to the child.
  mIsMouseEnterIntoWidgetEventSuppressed = true;
}

void BrowserParent::SendRealMouseEvent(WidgetMouseEvent& aEvent) {
  if (mIsDestroyed) {
    return;
  }

  // XXXedgar, if the synthesized mouse events could deliver to the correct
  // process directly (see
  // https://bugzilla.mozilla.org/show_bug.cgi?id=1549355), we probably don't
  // need to check mReason then.
  if (aEvent.mReason == WidgetMouseEvent::eReal) {
    if (aEvent.mMessage == eMouseExitFromWidget) {
      // Since we are leaving this remote target, so don't need to update
      // sLastMouseRemoteTarget, and if we are sLastMouseRemoteTarget, reset it
      // to null.
      BrowserParent::UnsetLastMouseRemoteTarget(this);
    } else {
      // Last remote target should not be changed without eMouseExitFromWidget.
      MOZ_ASSERT_IF(sLastMouseRemoteTarget, sLastMouseRemoteTarget == this);
      sLastMouseRemoteTarget = this;
    }
  }

  aEvent.mRefPoint = TransformParentToChild(aEvent);

  if (nsCOMPtr<nsIWidget> widget = GetWidget()) {
    // When we mouseenter the remote target, the remote target's cursor should
    // become the current cursor.  When we mouseexit, we stop.
    if (eMouseEnterIntoWidget == aEvent.mMessage) {
      mRemoteTargetSetsCursor = true;
      if (!EventStateManager::CursorSettingManagerHasLockedCursor()) {
        widget->SetCursor(mCursor);
        EventStateManager::ClearCursorSettingManager();
      }
    } else if (eMouseExitFromWidget == aEvent.mMessage) {
      mRemoteTargetSetsCursor = false;
    }
  }
  if (!mIsReadyToHandleInputEvents) {
    if (eMouseEnterIntoWidget == aEvent.mMessage) {
      mIsMouseEnterIntoWidgetEventSuppressed = true;
    } else if (eMouseExitFromWidget == aEvent.mMessage) {
      mIsMouseEnterIntoWidgetEventSuppressed = false;
    }
    return;
  }

  ScrollableLayerGuid guid;
  uint64_t blockId;
  ApzAwareEventRoutingToChild(&guid, &blockId, nullptr);

  bool isInputPriorityEventEnabled = Manager()->IsInputPriorityEventEnabled();

  if (mIsMouseEnterIntoWidgetEventSuppressed) {
    // In the case that the BrowserParent suppressed the eMouseEnterWidget event
    // due to its corresponding BrowserChild wasn't ready to handle it, we have
    // to resend it when the BrowserChild is ready.
    mIsMouseEnterIntoWidgetEventSuppressed = false;
    WidgetMouseEvent localEvent(aEvent);
    localEvent.mMessage = eMouseEnterIntoWidget;
    DebugOnly<bool> ret =
        isInputPriorityEventEnabled
            ? SendRealMouseEnterExitWidgetEvent(localEvent, guid, blockId)
            : SendNormalPriorityRealMouseEnterExitWidgetEvent(localEvent, guid,
                                                              blockId);
    NS_WARNING_ASSERTION(ret, "SendRealMouseEnterExitWidgetEvent() failed");
    MOZ_ASSERT(!ret || localEvent.HasBeenPostedToRemoteProcess());
  }

  if (eMouseMove == aEvent.mMessage) {
    if (aEvent.mReason == WidgetMouseEvent::eSynthesized) {
      DebugOnly<bool> ret =
          isInputPriorityEventEnabled
              ? SendSynthMouseMoveEvent(aEvent, guid, blockId)
              : SendNormalPrioritySynthMouseMoveEvent(aEvent, guid, blockId);
      NS_WARNING_ASSERTION(ret, "SendSynthMouseMoveEvent() failed");
      MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
      return;
    }

    if (!aEvent.mFlags.mIsSynthesizedForTests) {
      DebugOnly<bool> ret =
          isInputPriorityEventEnabled
              ? SendRealMouseMoveEvent(aEvent, guid, blockId)
              : SendNormalPriorityRealMouseMoveEvent(aEvent, guid, blockId);
      NS_WARNING_ASSERTION(ret, "SendRealMouseMoveEvent() failed");
      MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
      return;
    }

    DebugOnly<bool> ret =
        isInputPriorityEventEnabled
            ? SendRealMouseMoveEventForTests(aEvent, guid, blockId)
            : SendNormalPriorityRealMouseMoveEventForTests(aEvent, guid,
                                                           blockId);
    NS_WARNING_ASSERTION(ret, "SendRealMouseMoveEventForTests() failed");
    MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
    return;
  }

  if (eMouseEnterIntoWidget == aEvent.mMessage ||
      eMouseExitFromWidget == aEvent.mMessage) {
    DebugOnly<bool> ret =
        isInputPriorityEventEnabled
            ? SendRealMouseEnterExitWidgetEvent(aEvent, guid, blockId)
            : SendNormalPriorityRealMouseEnterExitWidgetEvent(aEvent, guid,
                                                              blockId);
    NS_WARNING_ASSERTION(ret, "SendRealMouseEnterExitWidgetEvent() failed");
    MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
    return;
  }

  DebugOnly<bool> ret =
      isInputPriorityEventEnabled
          ? aEvent.mClass == ePointerEventClass
                ? SendRealPointerButtonEvent(*aEvent.AsPointerEvent(), guid,
                                             blockId)
                : SendRealMouseButtonEvent(aEvent, guid, blockId)
      : aEvent.mClass == ePointerEventClass
          ? SendNormalPriorityRealPointerButtonEvent(*aEvent.AsPointerEvent(),
                                                     guid, blockId)
          : SendNormalPriorityRealMouseButtonEvent(aEvent, guid, blockId);
  NS_WARNING_ASSERTION(ret, "SendRealMouseButtonEvent() failed");
  MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
}

LayoutDeviceToCSSScale BrowserParent::GetLayoutDeviceToCSSScale() {
  Document* doc = (mFrameElement ? mFrameElement->OwnerDoc() : nullptr);
  nsPresContext* ctx = (doc ? doc->GetPresContext() : nullptr);
  return LayoutDeviceToCSSScale(
      ctx ? (float)ctx->AppUnitsPerDevPixel() / AppUnitsPerCSSPixel() : 0.0f);
}

bool BrowserParent::QueryDropLinksForVerification() {
  // Before sending the dragEvent, we query the links being dragged and
  // store them on the parent, to make sure the child can not modify links.
  RefPtr<nsIWidget> widget = GetTopLevelWidget();
  nsCOMPtr<nsIDragSession> dragSession = nsContentUtils::GetDragSession(widget);
  if (!dragSession) {
    NS_WARNING("No dragSession to query links for verification");
    return false;
  }

  RefPtr<DataTransfer> initialDataTransfer = dragSession->GetDataTransfer();
  if (!initialDataTransfer) {
    NS_WARNING("No initialDataTransfer to query links for verification");
    return false;
  }

  nsCOMPtr<nsIDroppedLinkHandler> dropHandler =
      do_GetService("@mozilla.org/content/dropped-link-handler;1");
  if (!dropHandler) {
    NS_WARNING("No dropHandler to query links for verification");
    return false;
  }

  // No more than one drop event can happen simultaneously; reset the link
  // verification array and store all links that are being dragged.
  mVerifyDropLinks.Clear();

  nsTArray<RefPtr<nsIDroppedLinkItem>> droppedLinkItems;
  dropHandler->QueryLinks(initialDataTransfer, droppedLinkItems);

  // Since the entire event is cancelled if one of the links is invalid,
  // we can store all links on the parent side without any prior
  // validation checks.
  nsresult rv = NS_OK;
  for (nsIDroppedLinkItem* item : droppedLinkItems) {
    nsString tmp;
    rv = item->GetUrl(tmp);
    if (NS_FAILED(rv)) {
      NS_WARNING("Failed to query url for verification");
      break;
    }
    mVerifyDropLinks.AppendElement(tmp);

    rv = item->GetName(tmp);
    if (NS_FAILED(rv)) {
      NS_WARNING("Failed to query name for verification");
      break;
    }
    mVerifyDropLinks.AppendElement(tmp);

    rv = item->GetType(tmp);
    if (NS_FAILED(rv)) {
      NS_WARNING("Failed to query type for verification");
      break;
    }
    mVerifyDropLinks.AppendElement(tmp);
  }
  if (NS_FAILED(rv)) {
    mVerifyDropLinks.Clear();
    return false;
  }
  return true;
}

void BrowserParent::SendRealDragEvent(WidgetDragEvent& aEvent,
                                      uint32_t aDragAction,
                                      uint32_t aDropEffect,
                                      nsIPrincipal* aPrincipal,
                                      nsIContentSecurityPolicy* aCsp) {
  if (mIsDestroyed || !mIsReadyToHandleInputEvents) {
    return;
  }
  MOZ_ASSERT(!Manager()->IsInputPriorityEventEnabled());
  aEvent.mRefPoint = TransformParentToChild(aEvent.mRefPoint);
  if (aEvent.mMessage == eDrop) {
    if (!QueryDropLinksForVerification()) {
      return;
    }
  }
  DebugOnly<bool> ret = PBrowserParent::SendRealDragEvent(
      aEvent, aDragAction, aDropEffect, aPrincipal, aCsp);
  NS_WARNING_ASSERTION(ret, "PBrowserParent::SendRealDragEvent() failed");
  MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
}

void BrowserParent::SendMouseWheelEvent(WidgetWheelEvent& aEvent) {
  if (mIsDestroyed || !mIsReadyToHandleInputEvents) {
    return;
  }

  ScrollableLayerGuid guid;
  uint64_t blockId;
  ApzAwareEventRoutingToChild(&guid, &blockId, nullptr);
  aEvent.mRefPoint = TransformParentToChild(aEvent.mRefPoint);
  DebugOnly<bool> ret =
      Manager()->IsInputPriorityEventEnabled()
          ? PBrowserParent::SendMouseWheelEvent(aEvent, guid, blockId)
          : PBrowserParent::SendNormalPriorityMouseWheelEvent(aEvent, guid,
                                                              blockId);

  NS_WARNING_ASSERTION(ret, "PBrowserParent::SendMouseWheelEvent() failed");
  MOZ_ASSERT(!ret || aEvent.HasBeenPostedToRemoteProcess());
}

mozilla::ipc::IPCResult BrowserParent::RecvDispatchWheelEvent(
    const mozilla::WidgetWheelEvent& aEvent) {
  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    return IPC_OK();
  }

  WidgetWheelEvent localEvent(aEvent);
  localEvent.mWidget = widget;
  localEvent.mRefPoint = TransformChildToParent(localEvent.mRefPoint);

  widget->DispatchInputEvent(&localEvent);
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvDispatchMouseEvent(
    const mozilla::WidgetMouseEvent& aEvent) {
  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    return IPC_OK();
  }

  WidgetMouseEvent localEvent(aEvent);
  localEvent.mWidget = widget;
  localEvent.mRefPoint = TransformChildToParent(localEvent.mRefPoint);

  widget->DispatchInputEvent(&localEvent);
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvDispatchKeyboardEvent(
    const mozilla::WidgetKeyboardEvent& aEvent) {
  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    return IPC_OK();
  }

  WidgetKeyboardEvent localEvent(aEvent);
  localEvent.mWidget = widget;
  localEvent.mRefPoint = TransformChildToParent(localEvent.mRefPoint);

  widget->DispatchInputEvent(&localEvent);
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvDispatchTouchEvent(
    const mozilla::WidgetTouchEvent& aEvent) {
  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    return IPC_OK();
  }

  WidgetTouchEvent localEvent(aEvent);
  localEvent.mWidget = widget;

  for (uint32_t i = 0; i < localEvent.mTouches.Length(); i++) {
    localEvent.mTouches[i]->mRefPoint =
        TransformChildToParent(localEvent.mTouches[i]->mRefPoint);
  }

  widget->DispatchInputEvent(&localEvent);
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvRequestNativeKeyBindings(
    const uint32_t& aType, const WidgetKeyboardEvent& aEvent,
    nsTArray<CommandInt>* aCommands) {
  MOZ_ASSERT(aCommands);
  MOZ_ASSERT(aCommands->IsEmpty());

  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  NativeKeyBindingsType keyBindingsType =
      static_cast<NativeKeyBindingsType>(aType);
  switch (keyBindingsType) {
    case NativeKeyBindingsType::SingleLineEditor:
    case NativeKeyBindingsType::MultiLineEditor:
    case NativeKeyBindingsType::RichTextEditor:
      break;
    default:
      return IPC_FAIL(this, "Invalid aType value");
  }

  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (!widget) {
    return IPC_OK();
  }

  WidgetKeyboardEvent localEvent(aEvent);
  localEvent.mWidget = widget;

  if (NS_FAILED(widget->AttachNativeKeyEvent(localEvent))) {
    return IPC_OK();
  }

  Maybe<WritingMode> writingMode;
  if (RefPtr<widget::TextEventDispatcher> dispatcher =
          widget->GetTextEventDispatcher()) {
    writingMode = dispatcher->MaybeQueryWritingModeAtSelection();
  }
  if (localEvent.InitEditCommandsFor(keyBindingsType, writingMode)) {
    *aCommands = localEvent.EditCommandsConstRef(keyBindingsType).Clone();
  }

  return IPC_OK();
}

class SynthesizedEventObserver : public nsIObserver {
  NS_DECL_ISUPPORTS

 public:
  SynthesizedEventObserver(BrowserParent* aBrowserParent,
                           const uint64_t& aObserverId)
      : mBrowserParent(aBrowserParent), mObserverId(aObserverId) {
    MOZ_ASSERT(mBrowserParent);
  }

  NS_IMETHOD Observe(nsISupports* aSubject, const char* aTopic,
                     const char16_t* aData) override {
    if (!mBrowserParent || !mObserverId) {
      // We already sent the notification, or we don't actually need to
      // send any notification at all.
      return NS_OK;
    }

    if (mBrowserParent->IsDestroyed()) {
      // If this happens it's probably a bug in the test that's triggering this.
      NS_WARNING(
          "BrowserParent was unexpectedly destroyed during event "
          "synthesization!");
    } else if (!mBrowserParent->SendNativeSynthesisResponse(
                   mObserverId, nsCString(aTopic))) {
      NS_WARNING("Unable to send native event synthesization response!");
    }
    // Null out browserParent to indicate we already sent the response
    mBrowserParent = nullptr;
    return NS_OK;
  }

 private:
  virtual ~SynthesizedEventObserver() = default;

  RefPtr<BrowserParent> mBrowserParent;
  uint64_t mObserverId;
};

NS_IMPL_ISUPPORTS(SynthesizedEventObserver, nsIObserver)

class MOZ_STACK_CLASS AutoSynthesizedEventResponder {
 public:
  AutoSynthesizedEventResponder(BrowserParent* aBrowserParent,
                                const uint64_t& aObserverId, const char* aTopic)
      : mObserver(new SynthesizedEventObserver(aBrowserParent, aObserverId)),
        mTopic(aTopic) {}

  ~AutoSynthesizedEventResponder() {
    // This may be a no-op if the observer already sent a response.
    mObserver->Observe(nullptr, mTopic, nullptr);
  }

  nsIObserver* GetObserver() { return mObserver; }

 private:
  nsCOMPtr<nsIObserver> mObserver;
  const char* mTopic;
};

mozilla::ipc::IPCResult BrowserParent::RecvSynthesizeNativeKeyEvent(
    const int32_t& aNativeKeyboardLayout, const int32_t& aNativeKeyCode,
    const uint32_t& aModifierFlags, const nsString& aCharacters,
    const nsString& aUnmodifiedCharacters, const uint64_t& aObserverId) {
  NS_ENSURE_TRUE(xpc::IsInAutomation(), IPC_FAIL(this, "Unexpected event"));

  AutoSynthesizedEventResponder responder(this, aObserverId, "keyevent");
  nsCOMPtr<nsIWidget> widget = GetWidget();
  if (widget) {
    widget->SynthesizeNativeKeyEvent(
        aNativeKeyboardLayout, aNativeKeyCode, aModifierFlags, aCharacters,
        aUnmodifiedCharacters, responder.GetObserver());
  }
  return IPC_OK();
}

mozilla::ipc::IPCResult BrowserParent::RecvSynthesizeNativeMouseEvent(
    const LayoutDeviceIntPoint& aPoint, const uint32_t& aNativeMessage,
    const int16_t& aButton, const uint32_t& aModifierFlags,
    const uint64_t& aObserverId) {
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