Animations: Introduce compositor AnimationPlayer and AnimationTimeline.

Source/core/animation/AnimationPlayer.h

Index: Source/core/animation/AnimationPlayer.h
diff --git a/Source/core/animation/AnimationPlayer.h b/Source/core/animation/AnimationPlayer.h
index ea016e22c22c1440b19f96c7720500de6f9c8714..55b58766c0a4c6cc38ad6cfbf34283ece965efeb 100644
--- a/Source/core/animation/AnimationPlayer.h
+++ b/Source/core/animation/AnimationPlayer.h
@@ -39,6 +39,8 @@
 #include "core/dom/DOMException.h"
 #include "core/events/EventTarget.h"
 #include "platform/heap/Handle.h"
+#include "public/platform/WebCompositorAnimationDelegate.h"
+#include "public/platform/WebCompositorAnimationPlayerClient.h"
 #include "wtf/RefPtr.h"
 
 namespace blink {
@@ -46,11 +48,14 @@ namespace blink {
 class AnimationTimeline;
 class Element;
 class ExceptionState;
+class WebCompositorAnimationPlayer;
 
 class AnimationPlayer final
-    : public EventTargetWithInlineData
-    , public RefCountedWillBeNoBase<AnimationPlayer>
-    , public ActiveDOMObject {
+    : public EventTargetWithInlineData,
+    public RefCountedWillBeNoBase<AnimationPlayer>,
+    public ActiveDOMObject,
+    public WebCompositorAnimationDelegate,
+    public WebCompositorAnimationPlayerClient {
     DEFINE_WRAPPERTYPEINFO();
     REFCOUNTED_EVENT_TARGET(AnimationPlayer);
     WILL_BE_USING_GARBAGE_COLLECTED_MIXIN(AnimationPlayer);
@@ -140,7 +145,8 @@ public:
     void setOutdated();
     bool outdated() { return m_outdated; }
 
-    bool canStartAnimationOnCompositor();
+    bool canStartAnimationOnCompositor() const;
+    bool isCandidateForAnimationOnCompositor() const;
     bool maybeStartAnimationOnCompositor();
     void cancelAnimationOnCompositor();
     void restartAnimationOnCompositor();
@@ -149,6 +155,10 @@ public:
     void setCompositorPending(bool sourceChanged = false);
     void notifyCompositorStartTime(double timelineTime);
     void notifyStartTime(double timelineTime);
+    // WebCompositorAnimationPlayerClient implementation.
+    WebCompositorAnimationPlayer* compositorPlayer() const override { return m_compositorPlayer.get(); }
+
+    void updateCompositedLayersAttachment();
 
     bool affects(const Element&, CSSPropertyID) const;
 
@@ -183,6 +193,16 @@ private:
     void beginUpdatingState();
     void endUpdatingState();
 
+    void createCompositorPlayer();
+    void destroyCompositorPlayer();
+    void attachCompositorTimeline();
+    void detachCompositorTimeline();
+    void attachCompositedLayers();
+    void detachCompositedLayers();
+    // WebCompositorAnimationDelegate implementation.
+    void notifyAnimationStarted(double monotonicTime, int group) override;
+    void notifyAnimationFinished(double monotonicTime, int group) override { }
+
     AnimationPlayState m_playState;
     double m_playbackRate;
     double m_startTime;
@@ -258,9 +278,11 @@ private:
     bool m_compositorPending;
     int m_compositorGroup;
 
+    OwnPtr<WebCompositorAnimationPlayer> m_compositorPlayer;
+    bool m_attachCompositedLayers;
+
     bool m_currentTimePending;
     bool m_stateIsBeingUpdated;
-
 };
 
 } // namespace blink