Revert of 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 175c9a4f49f218506549699fdcf7e447153ab0aa..9e3114393b434491eef11473c3bce08b3bfcc968 100644
--- a/cc/trees/layer_tree_impl.cc
+++ b/cc/trees/layer_tree_impl.cc
@@ -384,6 +384,11 @@ 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::PushPropertyTreesTo(LayerTreeImpl* target_tree) {