cc: Compute sublayer scale from effect tree

cc/trees/property_tree.h

Index: cc/trees/property_tree.h
diff --git a/cc/trees/property_tree.h b/cc/trees/property_tree.h
index b40c909ed08ab9cec8a24f3742045dc37f23e603..68a99767f0a13a888f40648dc67893d93357cbe8 100644
--- a/cc/trees/property_tree.h
+++ b/cc/trees/property_tree.h
@@ -273,6 +273,8 @@ struct CC_EXPORT EffectNodeData {
 
   FilterOperations background_filters;
 
+  gfx::Vector2dF sublayer_scale;
+
   bool has_render_surface;
   RenderSurfaceImpl* render_surface;
   bool has_copy_request;
@@ -604,6 +606,8 @@ class CC_EXPORT EffectTree final : public PropertyTree<EffectNode> {
 
   float EffectiveOpacity(const EffectNode* node) const;
 
+  void UpdateSublayerScale(EffectNode* node);
+
   void UpdateEffects(int id);
 
   void UpdateEffectChanged(EffectNode* node, EffectNode* parent_node);