Bug 1738971 - Part 1. Split out plumbing for AnimationFrameProvider from Document. r=dom-worker-reviewers,smaug

This patch splits out AnimationFrameProvider from the Document WebIDL to
allow the workers to implement it. It also splits out a helper class to
manage the requestAnimationFrame callbacks which may be reused on a
worker thread.

Differential Revision: https://phabricator.services.mozilla.com/D130262

dom/base/AnimationFrameProvider.cpp

@@ -0,0 +1,53 @@
+/* -*- 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 "mozilla/dom/AnimationFrameProvider.h"
+#include "nsThreadUtils.h"
+
+namespace mozilla::dom {
+
+FrameRequest::FrameRequest(FrameRequestCallback& aCallback, int32_t aHandle)
+    : mCallback(&aCallback), mHandle(aHandle) {
+  LogFrameRequestCallback::LogDispatch(mCallback);
+}
+
+FrameRequest::~FrameRequest() = default;
+
+nsresult FrameRequestManager::Schedule(FrameRequestCallback& aCallback,
+                                       int32_t* aHandle) {
+  if (mCallbackCounter == INT32_MAX) {
+    // Can't increment without overflowing; bail out
+    return NS_ERROR_NOT_AVAILABLE;
+  }
+  int32_t newHandle = ++mCallbackCounter;
+
+  mCallbacks.AppendElement(FrameRequest(aCallback, newHandle));
+
+  *aHandle = newHandle;
+  return NS_OK;
+}
+
+bool FrameRequestManager::Cancel(int32_t aHandle) {
+  // mCallbacks is stored sorted by handle
+  if (mCallbacks.RemoveElementSorted(aHandle)) {
+    return true;
+  }
+
+  Unused << mCanceledCallbacks.put(aHandle);
+  return false;
+}
+
+void FrameRequestManager::Unlink() { mCallbacks.Clear(); }
+
+void FrameRequestManager::Traverse(nsCycleCollectionTraversalCallback& aCB) {
+  for (auto& i : mCallbacks) {
+    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(aCB,
+                                       "FrameRequestManager::mCallbacks[i]");
+    aCB.NoteXPCOMChild(i.mCallback);
+  }
+}
+
+}  // namespace mozilla::dom

dom/base/AnimationFrameProvider.h

@@ -0,0 +1,78 @@
+/* -*- 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/. */
+
+#ifndef mozilla_dom_AnimationFrameProvider_h
+#define mozilla_dom_AnimationFrameProvider_h
+
+#include "mozilla/dom/AnimationFrameProviderBinding.h"
+#include "mozilla/HashTable.h"
+#include "mozilla/RefPtr.h"
+#include "nsTArray.h"
+
+namespace mozilla::dom {
+
+struct FrameRequest {
+  FrameRequest(FrameRequestCallback& aCallback, int32_t aHandle);
+  ~FrameRequest();
+
+  // Comparator operators to allow RemoveElementSorted with an
+  // integer argument on arrays of FrameRequest
+  bool operator==(int32_t aHandle) const { return mHandle == aHandle; }
+  bool operator<(int32_t aHandle) const { return mHandle < aHandle; }
+
+  RefPtr<FrameRequestCallback> mCallback;
+  int32_t mHandle;
+};
+
+class FrameRequestManager {
+ public:
+  FrameRequestManager() = default;
+  ~FrameRequestManager() = default;
+
+  nsresult Schedule(FrameRequestCallback& aCallback, int32_t* aHandle);
+  bool Cancel(int32_t aHandle);
+
+  bool IsEmpty() const { return mCallbacks.IsEmpty(); }
+
+  bool IsCanceled(int32_t aHandle) const {
+    return !mCanceledCallbacks.empty() && mCanceledCallbacks.has(aHandle);
+  }
+
+  void Take(nsTArray<FrameRequest>& aCallbacks) {
+    aCallbacks = std::move(mCallbacks);
+    mCanceledCallbacks.clear();
+  }
+
+  void Unlink();
+
+  void Traverse(nsCycleCollectionTraversalCallback& aCB);
+
+ private:
+  nsTArray<FrameRequest> mCallbacks;
+
+  // The set of frame request callbacks that were canceled but which we failed
+  // to find in mFrameRequestCallbacks.
+  HashSet<int32_t> mCanceledCallbacks;
+
+  /**
+   * The current frame request callback handle
+   */
+  int32_t mCallbackCounter = 0;
+};
+
+inline void ImplCycleCollectionUnlink(FrameRequestManager& aField) {
+  aField.Unlink();
+}
+
+inline void ImplCycleCollectionTraverse(
+    nsCycleCollectionTraversalCallback& aCallback, FrameRequestManager& aField,
+    const char* aName, uint32_t aFlags) {
+  aField.Traverse(aCallback);
+}
+
+}  // namespace mozilla::dom
+
+#endif

dom/base/Document.cpp

@@ -1252,14 +1252,6 @@ void Document::SelectorCache::NotifyExpired(SelectorCacheKey* aSelector) {
   delete aSelector;
 }
 
-Document::FrameRequest::FrameRequest(FrameRequestCallback& aCallback,
-                                     int32_t aHandle)
-    : mCallback(&aCallback), mHandle(aHandle) {
-  LogFrameRequestCallback::LogDispatch(mCallback);
-}
-
-Document::FrameRequest::~FrameRequest() = default;
-
 Document::PendingFrameStaticClone::~PendingFrameStaticClone() = default;
 
 // ==================================================================
@@ -1412,7 +1404,6 @@ Document::Document(const char* aContentType)
       mPreloadPictureDepth(0),
       mEventsSuppressed(0),
       mIgnoreDestructiveWritesCounter(0),
-      mFrameRequestCallbackCounter(0),
       mStaticCloneCount(0),
       mWindow(nullptr),
       mBFCacheEntry(nullptr),
@@ -2446,15 +2437,11 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(Document)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mMidasCommandManager)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mAll)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mDocGroup)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mFrameRequestManager)
 
   // Traverse all our nsCOMArrays.
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPreloadingImages)
 
-  for (uint32_t i = 0; i < tmp->mFrameRequestCallbacks.Length(); ++i) {
-    NS_CYCLE_COLLECTION_NOTE_EDGE_NAME(cb, "mFrameRequestCallbacks[i]");
-    cb.NoteXPCOMChild(tmp->mFrameRequestCallbacks[i].mCallback);
-  }
-
   // Traverse animation components
   if (tmp->mAnimationController) {
     tmp->mAnimationController->Traverse(&cb);
@@ -2600,7 +2587,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(Document)
   delete tmp->mSubDocuments;
   tmp->mSubDocuments = nullptr;
 
-  tmp->mFrameRequestCallbacks.Clear();
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mFrameRequestManager)
   MOZ_RELEASE_ASSERT(!tmp->mFrameRequestCallbacksScheduled,
                      "How did we get here without our presshell going away "
                      "first?");
@@ -6889,7 +6876,7 @@ void Document::UpdateFrameRequestCallbackSchedulingState(
   // WouldScheduleFrameRequestCallbacks() instead of adding more stuff to this
   // condition.
   bool shouldBeScheduled =
-      WouldScheduleFrameRequestCallbacks() && !mFrameRequestCallbacks.IsEmpty();
+      WouldScheduleFrameRequestCallbacks() && !mFrameRequestManager.IsEmpty();
   if (shouldBeScheduled == mFrameRequestCallbacksScheduled) {
     // nothing to do
     return;
@@ -6910,8 +6897,7 @@ void Document::UpdateFrameRequestCallbackSchedulingState(
 
 void Document::TakeFrameRequestCallbacks(nsTArray<FrameRequest>& aCallbacks) {
   MOZ_ASSERT(aCallbacks.IsEmpty());
-  aCallbacks = std::move(mFrameRequestCallbacks);
-  mCanceledFrameRequestCallbacks.clear();
+  mFrameRequestManager.Take(aCallbacks);
   // No need to manually remove ourselves from the refresh driver; it will
   // handle that part.  But we do have to update our state.
   mFrameRequestCallbacksScheduled = false;
@@ -13210,31 +13196,23 @@ void Document::UnlinkOriginalDocumentIfStatic() {
 
 nsresult Document::ScheduleFrameRequestCallback(FrameRequestCallback& aCallback,
                                                 int32_t* aHandle) {
-  if (mFrameRequestCallbackCounter == INT32_MAX) {
-    // Can't increment without overflowing; bail out
-    return NS_ERROR_NOT_AVAILABLE;
+  nsresult rv = mFrameRequestManager.Schedule(aCallback, aHandle);
+  if (NS_FAILED(rv)) {
+    return rv;
   }
-  int32_t newHandle = ++mFrameRequestCallbackCounter;
 
-  mFrameRequestCallbacks.AppendElement(FrameRequest(aCallback, newHandle));
   UpdateFrameRequestCallbackSchedulingState();
-
-  *aHandle = newHandle;
   return NS_OK;
 }
 
 void Document::CancelFrameRequestCallback(int32_t aHandle) {
-  // mFrameRequestCallbacks is stored sorted by handle
-  if (mFrameRequestCallbacks.RemoveElementSorted(aHandle)) {
+  if (mFrameRequestManager.Cancel(aHandle)) {
     UpdateFrameRequestCallbackSchedulingState();
-  } else {
-    Unused << mCanceledFrameRequestCallbacks.put(aHandle);
   }
 }
 
 bool Document::IsCanceledFrameRequestCallback(int32_t aHandle) const {
-  return !mCanceledFrameRequestCallbacks.empty() &&
-         mCanceledFrameRequestCallbacks.has(aHandle);
+  return mFrameRequestManager.IsCanceled(aHandle);
 }
 
 nsresult Document::GetStateObject(nsIVariant** aState) {

dom/base/Document.h

@@ -45,6 +45,7 @@
 #include "mozilla/UseCounter.h"
 #include "mozilla/WeakPtr.h"
 #include "mozilla/css/StylePreloadKind.h"
+#include "mozilla/dom/AnimationFrameProvider.h"
 #include "mozilla/dom/DispatcherTrait.h"
 #include "mozilla/dom/DocumentOrShadowRoot.h"
 #include "mozilla/dom/Element.h"
@@ -3103,19 +3104,6 @@ class Document : public nsINode,
 
   SVGSVGElement* GetSVGRootElement() const;
 
-  struct FrameRequest {
-    FrameRequest(FrameRequestCallback& aCallback, int32_t aHandle);
-    ~FrameRequest();
-
-    // Comparator operators to allow RemoveElementSorted with an
-    // integer argument on arrays of FrameRequest
-    bool operator==(int32_t aHandle) const { return mHandle == aHandle; }
-    bool operator<(int32_t aHandle) const { return mHandle < aHandle; }
-
-    RefPtr<FrameRequestCallback> mCallback;
-    int32_t mHandle;
-  };
-
   nsresult ScheduleFrameRequestCallback(FrameRequestCallback& aCallback,
                                         int32_t* aHandle);
   void CancelFrameRequestCallback(int32_t aHandle);
@@ -4985,11 +4973,6 @@ class Document : public nsINode,
    */
   uint32_t mIgnoreDestructiveWritesCounter;
 
-  /**
-   * The current frame request callback handle
-   */
-  int32_t mFrameRequestCallbackCounter;
-
   // Count of live static clones of this document.
   uint32_t mStaticCloneCount;
 
@@ -5011,11 +4994,7 @@ class Document : public nsINode,
 
   nsCOMPtr<nsIDocumentEncoder> mCachedEncoder;
 
-  nsTArray<FrameRequest> mFrameRequestCallbacks;
-
-  // The set of frame request callbacks that were canceled but which we failed
-  // to find in mFrameRequestCallbacks.
-  HashSet<int32_t> mCanceledFrameRequestCallbacks;
+  FrameRequestManager mFrameRequestManager;
 
   // This object allows us to evict ourself from the back/forward cache.  The
   // pointer is non-null iff we're currently in the bfcache.

dom/base/moz.build

@@ -148,6 +148,7 @@ EXPORTS.mozilla.dom += [
     "!UseCounterWorkerList.h",
     "AbstractRange.h",
     "AncestorIterator.h",
+    "AnimationFrameProvider.h",
     "AnonymousContent.h",
     "Attr.h",
     "AutoPrintEventDispatcher.h",
@@ -295,6 +296,7 @@ if CONFIG["FUZZING"]:
 
 UNIFIED_SOURCES += [
     "AbstractRange.cpp",
+    "AnimationFrameProvider.cpp",
     "AnonymousContent.cpp",
     "Attr.cpp",
     "AttrArray.cpp",

dom/webidl/AnimationFrameProvider.webidl

@@ -0,0 +1,15 @@
+/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* 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/.
+ *
+ * The origin of this IDL file is
+ * https://html.spec.whatwg.org/multipage/imagebitmap-and-animations.html#animation-frames
+ */
+
+callback FrameRequestCallback = void (DOMHighResTimeStamp time);
+
+interface mixin AnimationFrameProvider {
+  [Throws] long requestAnimationFrame(FrameRequestCallback callback);
+  [Throws] void cancelAnimationFrame(long handle);
+};

dom/webidl/Window.webidl

@@ -386,12 +386,8 @@ partial interface Window {
   [Throws, NeedsCallerType] attribute any outerHeight;
 };
 
-// https://dvcs.w3.org/hg/webperf/raw-file/tip/specs/RequestAnimationFrame/Overview.html
-partial interface Window {
-  [Throws] long requestAnimationFrame(FrameRequestCallback callback);
-  [Throws] void cancelAnimationFrame(long handle);
-};
-callback FrameRequestCallback = void (DOMHighResTimeStamp time);
+// https://html.spec.whatwg.org/multipage/imagebitmap-and-animations.html#animation-frames
+Window includes AnimationFrameProvider;
 
 // https://dvcs.w3.org/hg/webperf/raw-file/tip/specs/NavigationTiming/Overview.html
 partial interface Window {

dom/webidl/moz.build

@@ -403,6 +403,7 @@ WEBIDL_FILES = [
     "Animatable.webidl",
     "AnimationEffect.webidl",
     "AnimationEvent.webidl",
+    "AnimationFrameProvider.webidl",
     "AnimationTimeline.webidl",
     "AnonymousContent.webidl",
     "AppInfo.webidl",

gfx/vr/ipc/VRManagerChild.h

@@ -9,7 +9,7 @@
 
 #include "nsISupportsImpl.h"
 #include "mozilla/Attributes.h"
-#include "mozilla/dom/WindowBinding.h"  // For FrameRequestCallback
+#include "mozilla/dom/AnimationFrameProviderBinding.h"
 #include "mozilla/dom/WebXRBinding.h"
 #include "mozilla/dom/XRFrame.h"
 #include "mozilla/gfx/PVRManagerChild.h"

layout/base/nsRefreshDriver.cpp

@@ -1890,7 +1890,7 @@ struct DocumentFrameCallbacks {
   explicit DocumentFrameCallbacks(Document* aDocument) : mDocument(aDocument) {}
 
   RefPtr<Document> mDocument;
-  nsTArray<Document::FrameRequest> mCallbacks;
+  nsTArray<FrameRequest> mCallbacks;
 };
 
 static bool HasPendingAnimations(PresShell* aPresShell) {