Compute if a layer is clipped outside CalcDrawProps

cc/trees/property_tree_builder.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "cc/trees/property_tree_builder.h"
 
 #include <map>
 #include <set>
 
 #include "cc/base/math_util.h"
@@ skipping 127 matching lines @@
         data_for_children->render_target->transform_tree_index();
     node.owner_id = layer->id();
 
     data_for_children->clip_tree_parent =
         data_for_children->clip_tree->Insert(node, parent_id);
   }
 
   layer->SetClipTreeIndex(
       has_unclipped_surface ? 0 : data_for_children->clip_tree_parent);
 
+  // TODO(jaydasika): This value depends on whether a layer has a render
+  // surface or not. When building property trees becomes independant of
+  // render surfaces(see http://crbug.com/504467), this should move.

[Ian Vollick, 2015/07/07 19:09:39]

Hey, I wanted to mention here what we'd discussed offline -- that constructing
clip trees (unlike transform trees) will likely come after layerization and
render surface determination. I've made a comment on the liked bug. This second
sentence should probably be ditched?

[jaydasika, 2015/07/07 19:15:56]

If render surfaces are determined before building clip tree, the whole comment
can be ditched as we don't need to move is_clipped computation 

+  layer->set_is_clipped_from_property_tree(
+      data_for_children->ancestor_clips_subtree);
+
   // TODO(awoloszyn): Right now when we hit a node with a replica, we reset the
   // clip for all children since we may need to draw. We need to figure out a
   // better way, since we will need both the clipped and unclipped versions.
 }
 
 template <typename LayerType>
 bool AddTransformNodeIfNeeded(
     const DataForRecursion<LayerType>& data_from_ancestor,
     LayerType* layer,
     DataForRecursion<LayerType>* data_for_children) {
@@ skipping 339 matching lines @@
     const gfx::Rect& viewport,
     const gfx::Transform& device_transform,
     PropertyTrees* property_trees) {
   BuildPropertyTreesTopLevelInternal(
       root_layer, page_scale_layer, inner_viewport_scroll_layer,
       outer_viewport_scroll_layer, page_scale_factor, device_scale_factor,
       viewport, device_transform, property_trees);
 }
 
 }  // namespace cc