Web Animations: Make AnimationPlayer an ActiveDOMObject

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 2d1fd6c509dfb4166b46253feeff789e2a18218c..230f639687d9dc83a8ef1536556b7fa3d5c04ee5 100644
--- a/Source/core/animation/AnimationPlayer.h
+++ b/Source/core/animation/AnimationPlayer.h
@@ -32,6 +32,7 @@
 #define AnimationPlayer_h
 
 #include "core/animation/AnimationSource.h"
+#include "core/dom/ActiveDOMObject.h"
 #include "core/events/EventTarget.h"
 #include "wtf/RefPtr.h"
 
@@ -40,7 +41,9 @@ namespace WebCore {
 class AnimationTimeline;
 class ExceptionState;
 
-class AnimationPlayer FINAL : public RefCountedWillBeRefCountedGarbageCollected<AnimationPlayer>, public EventTargetWithInlineData {
+class AnimationPlayer FINAL : public RefCountedWillBeRefCountedGarbageCollected<AnimationPlayer>
+    , public ActiveDOMObject
+    , public EventTargetWithInlineData {
     DEFINE_EVENT_TARGET_REFCOUNTING(RefCountedWillBeRefCountedGarbageCollected<AnimationPlayer>);
 public:
 
@@ -78,6 +81,8 @@ public:
 
     virtual const AtomicString& interfaceName() const OVERRIDE;
     virtual ExecutionContext* executionContext() const OVERRIDE;
+    virtual bool hasPendingActivity() const OVERRIDE;

[haraken, 2014/05/23 07:15:05]

Don't we need to override ActiveDOMObject::stop()/resume()? I guess you need to
clear the event when the ActiveDOMObject is stopped, for example.

[dstockwell, 2014/05/26 00:47:50]

Yes, I suppose stop() is necessary. suspend/resume are handled by
ScriptedAnimationController.

[haraken, 2014/05/26 01:16:09]

Makes sense.

- I'm just curious, but why are suspend/resume handled by
ScriptedAnimationController instead of using the infrastructure of
ActiveDOMObject?

- ScriptedAnimationController's suspend/resume does nothing about
AnimationPlayer. This is expected, right? (For example, you don't need to clear
m_pendingFinishedEvent when the Document is suspended.)

[dstockwell, 2014/05/26 01:32:40]

There's nothing that we need to suspend here. Animation is not involved with
ActiveDOMObject, it's just the event dispatch that we need to be concerned with,
and it's the ScriptedAnimationController that does the event dispatch.
Right, we don't need to clear it on suspend. We're just using
m_pendingFinishedEvent to track the current event, it would still be dispatched
after suspend/resume for example.

+    virtual bool dispatchEvent(PassRefPtrWillBeRawPtr<Event>) OVERRIDE;
 
     double playbackRate() const { return m_playbackRate; }
     void setPlaybackRate(double);
@@ -177,6 +182,10 @@ private:
     bool m_outdated;
 
     bool m_finished;
+    // Holds a 'finished' event queued for asynchronous dispatch via the
+    // ScriptedAnimationController. This object remains active until the
+    // event is actually dispatched.
+    RefPtrWillBeMember<Event> m_pendingFinishedEvent;
 };
 
 } // namespace