Allow animations with inactive observers to reach the Starting state

cc/test/animation_test_common.cc

Index: cc/test/animation_test_common.cc
diff --git a/cc/test/animation_test_common.cc b/cc/test/animation_test_common.cc
index 84f91348a2beff192fdf47d40078fb83b4d6989e..a667c1b7abc284c2d2dbdc4033696635b93c467d 100644
--- a/cc/test/animation_test_common.cc
+++ b/cc/test/animation_test_common.cc
@@ -164,6 +164,10 @@ bool FakeLayerAnimationValueObserver::IsActive() const {
   return true;
 }
 
+bool FakeInactiveLayerAnimationValueObserver::IsActive() const {
+  return false;
+}
+
 scoped_ptr<cc::AnimationCurve> FakeFloatTransition::Clone() const {
   return make_scoped_ptr(
       new FakeFloatTransition(*this)).PassAs<cc::AnimationCurve>();