cc : Don't draw animating layers which are transparent but raster them.

cc/trees/layer_tree_impl.cc

Index: cc/trees/layer_tree_impl.cc
diff --git a/cc/trees/layer_tree_impl.cc b/cc/trees/layer_tree_impl.cc
index dc9b4e9bfce64176681353802396ee24b174597e..56afebdf2d4bdcc1836d93f4ac891ef948637146 100644
--- a/cc/trees/layer_tree_impl.cc
+++ b/cc/trees/layer_tree_impl.cc
@@ -371,11 +371,6 @@ void LayerTreeImpl::SetPropertyTrees(PropertyTrees* property_trees) {
   property_trees_.is_main_thread = false;
   property_trees_.is_active = IsActiveTree();
   property_trees_.transform_tree.set_source_to_parent_updates_allowed(false);
-  // The value of some effect node properties (like is_drawn) depends on
-  // whether we are on the active tree or not. So, we need to update the
-  // effect tree.
-  if (IsActiveTree())
-    property_trees_.effect_tree.set_needs_update(true);
 }
 
 void LayerTreeImpl::PushPropertiesTo(LayerTreeImpl* target_tree) {