Web Animations: Add an event delegate to allow different forms of event dispatch

Source/core/animation/Animation.cpp

Index: Source/core/animation/Animation.cpp
diff --git a/Source/core/animation/Animation.cpp b/Source/core/animation/Animation.cpp
index 3c833ddea7c779f0a17df99919ba0fee27ce3a21..957ee730b0874481b2c719bf7412d168e7891274 100644
--- a/Source/core/animation/Animation.cpp
+++ b/Source/core/animation/Animation.cpp
@@ -43,7 +43,7 @@ PassRefPtr<Animation> Animation::create(PassRefPtr<Element> target, PassRefPtr<A
 }
 
 Animation::Animation(PassRefPtr<Element> target, PassRefPtr<AnimationEffect> effect, const Timing& timing)
-    : TimedItem(timing)
+    : TimedItem(timing, nullptr)

[pdr., 2013/08/01 21:11:16]

Would it be useful to change the TimedItem to use a default value of nullptr for
the event delegate?

[dstockwell, 2013/08/02 00:23:26]

Done.

     , m_target(target)
     , m_effect(effect)
     , m_activeInAnimationStack(false)