Determine a layer's IsAffectedByPageScale property without using Layer Tree

cc/layers/layer_impl.cc

 // Copyright 2012 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/layers/layer_impl.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <utility>
@@ skipping 680 matching lines @@
     frame_timing_requests_dirty_ = false;
   }
 
   // Reset any state that should be cleared for the next update.
   stacking_order_changed_ = false;
   update_rect_ = gfx::Rect();
   needs_push_properties_ = false;
   num_dependents_need_push_properties_ = 0;
 }
 
+bool LayerImpl::IsAffectedByPageScale() const {
+  TransformTree& transform_tree =
+      layer_tree_impl()->property_trees()->transform_tree;
+  return transform_tree.Node(transform_tree_index())
+      ->data.in_subtree_of_page_scale_layer;
+}
+
 gfx::Vector2dF LayerImpl::FixedContainerSizeDelta() const {
   LayerImpl* scroll_clip_layer =
       layer_tree_impl()->LayerById(scroll_clip_layer_id_);
   if (!scroll_clip_layer)
     return gfx::Vector2dF();
 
   return scroll_clip_layer->bounds_delta();
 }
 
 base::DictionaryValue* LayerImpl::LayerTreeAsJson() const {
@@ skipping 1189 matching lines @@
            .layer_transforms_should_scale_layer_contents) {
     return default_scale;
   }
 
   gfx::Vector2dF transform_scales = MathUtil::ComputeTransform2dScaleComponents(
       DrawTransform(), default_scale);
   return std::max(transform_scales.x(), transform_scales.y());
 }
 
 }  // namespace cc