CC Animations: Port Impl-only-scrolling to use compositor animation timelines.

cc/trees/layer_tree_host_impl.cc

Index: cc/trees/layer_tree_host_impl.cc
diff --git a/cc/trees/layer_tree_host_impl.cc b/cc/trees/layer_tree_host_impl.cc
index e0eea72afca29a3464f1970cbde346478249a039..d9770b8c202ed9335124d6fcbccc143cf2476f3f 100644
--- a/cc/trees/layer_tree_host_impl.cc
+++ b/cc/trees/layer_tree_host_impl.cc
@@ -3479,6 +3479,10 @@ void LayerTreeHostImpl::ScrollAnimationCreate(
     LayerImpl* layer_impl,
     const gfx::ScrollOffset& target_offset,
     const gfx::ScrollOffset& current_offset) {
+  if (animation_timeline_)
+    return animation_timeline_->ScrollAnimationCreate(
+        layer_impl->id(), target_offset, current_offset);
+
   scoped_ptr<ScrollOffsetAnimationCurve> curve =
       ScrollOffsetAnimationCurve::Create(target_offset,
                                          EaseInOutTimingFunction::Create());
@@ -3495,6 +3499,11 @@ void LayerTreeHostImpl::ScrollAnimationCreate(
 bool LayerTreeHostImpl::ScrollAnimationUpdateTarget(
     LayerImpl* layer_impl,
     const gfx::Vector2dF& scroll_delta) {
+  if (animation_timeline_)
+    return animation_timeline_->ScrollAnimationUpdateTarget(
+        layer_impl->id(), scroll_delta, layer_impl->MaxScrollOffset(),
+        CurrentBeginFrameArgs().frame_time);
+
   Animation* animation =
       layer_impl->layer_animation_controller()
           ? layer_impl->layer_animation_controller()->GetAnimation(