cc: Directly use property trees to calculate clip rect

cc/trees/layer_tree_settings.h

 // Copyright 2011 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.
 
 #ifndef CC_TREES_LAYER_TREE_SETTINGS_H_
 #define CC_TREES_LAYER_TREE_SETTINGS_H_
 
 #include <stddef.h>
 
 #include <vector>
@@ skipping 65 matching lines @@
   size_t max_memory_for_prepaint_percentage;
   bool strict_layer_property_change_checking;
   bool use_zero_copy;
   bool use_partial_raster;
   bool enable_elastic_overscroll;
   // An array of image texture targets for each GpuMemoryBuffer format.
   std::vector<unsigned> use_image_texture_targets;
   bool ignore_root_layer_flings;
   size_t scheduled_raster_task_limit;
   bool use_occlusion_for_tile_prioritization;
+  bool verify_clip_tree_calculations;
   bool image_decode_tasks_enabled;
   bool wait_for_beginframe_interval;
   bool abort_commit_before_output_surface_creation;
   bool use_mouse_wheel_gestures;
   int max_staging_buffer_usage_in_bytes;
   ManagedMemoryPolicy memory_policy_;
 
   LayerTreeDebugState initial_debug_state;
 };
 
 }  // namespace cc
 
 #endif  // CC_TREES_LAYER_TREE_SETTINGS_H_