Add AnimationTimingProperties dictionary

Source/core/animation/ComputedTimingProperties.idl

Index: Source/core/animation/ComputedTimingProperties.idl
diff --git a/Source/core/animation/ComputedTimingProperties.idl b/Source/core/animation/ComputedTimingProperties.idl
index f480041de7affcc582b83eca04ca4a0afadd2e80..d5e8e498f91c7e19459953539a7a3de48adf52f2 100644
--- a/Source/core/animation/ComputedTimingProperties.idl
+++ b/Source/core/animation/ComputedTimingProperties.idl
@@ -2,26 +2,13 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// FIXME: Should extend AnimationTimingProperties
 [
     TypeChecking=Unrestricted,
-] dictionary ComputedTimingProperties {
+] dictionary ComputedTimingProperties : AnimationTimingProperties {
     double              startTime;
     unrestricted double endTime;
     unrestricted double activeDuration;
     double?             localTime;
     unrestricted double timeFraction;
     unsigned long?      currentIteration;
-
-    // FIXME: These should be inherited from AnimationTimingProperties
-    double                             delay = 0;
-    double                             endDelay = 0;
-    DOMString                          fill = "auto";
-    double                             iterationStart = 0.0;
-    unrestricted double                iterations = 1.0;
-    // FIXME: Default should be 'auto'
-    (unrestricted double or DOMString) duration;
-    double                             playbackRate = 1.0;
-    DOMString                          direction = "normal";
-    DOMString                          easing = "linear";
 };