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

cc/trees/property_tree.cc

Index: cc/trees/property_tree.cc
diff --git a/cc/trees/property_tree.cc b/cc/trees/property_tree.cc
index 2ede29ec25e6b40b2327791d2f63166dadc37c2a..f450baa7067a5b3aa83fa9b6f08a201f17eb2e24 100644
--- a/cc/trees/property_tree.cc
+++ b/cc/trees/property_tree.cc
@@ -798,12 +798,13 @@ void EffectTree::UpdateIsDrawn(EffectNode* node, EffectNode* parent_node) {
   // 1) Nodes that contribute to copy requests, whether hidden or not, must be
   //    drawn.
   // 2) Nodes that have a background filter.
-  // 3) Nodes with animating screen space opacity are drawn if their parent is
-  //    drawn irrespective of their opacity.
+  // 3) Nodes with animating screen space opacity on main thread or pending tree
+  //    are drawn if their parent is drawn irrespective of their opacity.
   if (node->has_copy_request)
     node->is_drawn = true;
   else if (EffectiveOpacity(node) == 0.f &&
-           !node->has_potential_opacity_animation &&
+           (!node->has_potential_opacity_animation ||
+            property_trees()->is_active) &&
            node->background_filters.IsEmpty())
     node->is_drawn = false;
   else if (parent_node)