Share animations from compositor to main thread.

cc/trees/layer_tree_impl.h

Index: cc/trees/layer_tree_impl.h
diff --git a/cc/trees/layer_tree_impl.h b/cc/trees/layer_tree_impl.h
index f9f1ba1d39c3b7fb6c4216128f53f75de759aa71..87c1429ce08904dc8770b8172a4e01b723c4f8f6 100644
--- a/cc/trees/layer_tree_impl.h
+++ b/cc/trees/layer_tree_impl.h
@@ -112,6 +112,9 @@ class CC_EXPORT LayerTreeImpl {
   bool RequiresHighResToDraw() const;
   bool SmoothnessTakesPriority() const;
   VideoFrameControllerClient* GetVideoFrameControllerClient() const;
+  AnimationHost* animation_host() const {
+    return layer_tree_host_impl_->animation_host();
+  }
 
   // Tree specific methods exposed to layer-impl tree.
   // ---------------------------------------------------------------------------
@@ -417,6 +420,7 @@ class CC_EXPORT LayerTreeImpl {
 
   bool FilterIsAnimatingOnImplOnly(const LayerImpl* layer) const;
   bool OpacityIsAnimatingOnImplOnly(const LayerImpl* layer) const;
+  bool ScrollOffsetIsAnimatingOnImplOnly(const LayerImpl* layer) const;
   bool TransformIsAnimatingOnImplOnly(const LayerImpl* layer) const;
 
   bool AnimationsPreserveAxisAlignment(const LayerImpl* layer) const;