Use the iterator for DebugRectHistory

cc/debug/debug_rect_history.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/debug/debug_rect_history.h"
 
 #include <stddef.h>
 
 #include "cc/base/math_util.h"
 #include "cc/layers/layer_impl.h"
 #include "cc/layers/layer_iterator.h"
+#include "cc/layers/layer_list_iterator.h"
 #include "cc/layers/layer_utils.h"
 #include "cc/layers/render_surface_impl.h"
 #include "cc/trees/damage_tracker.h"
 #include "cc/trees/layer_tree_host.h"
 #include "cc/trees/layer_tree_host_common.h"
 #include "cc/trees/layer_tree_impl.h"
 #include "ui/gfx/geometry/rect_conversions.h"
 
 namespace cc {
 
@@ skipping 36 matching lines @@
   if (debug_state.show_surface_damage_rects)
     SaveSurfaceDamageRects(render_surface_layer_list);
 
   if (debug_state.show_screen_space_rects)
     SaveScreenSpaceRects(render_surface_layer_list);
 
   if (debug_state.show_layer_animation_bounds_rects)
     SaveLayerAnimationBoundsRects(render_surface_layer_list);
 }
 
-void DebugRectHistory::SavePaintRects(LayerImpl* layer) {
+void DebugRectHistory::SavePaintRects(LayerImpl* root_layer) {
   // We would like to visualize where any layer's paint rect (update rect) has
   // changed, regardless of whether this layer is skipped for actual drawing or
-  // not. Therefore we traverse recursively over all layers, not just the render
-  // surface list.
+  // not. Therefore we traverse over all layers, not just the render surface
+  // list.
+  for (auto* layer : *root_layer->layer_tree_impl()) {
+    Region invalidation_region = layer->GetInvalidationRegion();
+    if (invalidation_region.IsEmpty() || !layer->DrawsContent())
+      continue;
 
-  Region invalidation_region = layer->GetInvalidationRegion();
-  if (!invalidation_region.IsEmpty() && layer->DrawsContent()) {
     for (Region::Iterator it(invalidation_region); it.has_rect(); it.next()) {
       debug_rects_.push_back(DebugRect(
           PAINT_RECT_TYPE, MathUtil::MapEnclosingClippedRect(
                                layer->ScreenSpaceTransform(), it.rect())));
     }
   }
-
-  for (unsigned i = 0; i < layer->children().size(); ++i)
-    SavePaintRects(layer->children()[i].get());
 }
 
 void DebugRectHistory::SavePropertyChangedRects(
     const LayerImplList& render_surface_layer_list,
     LayerImpl* hud_layer) {
   for (size_t i = 0; i < render_surface_layer_list.size(); ++i) {
     size_t surface_index = render_surface_layer_list.size() - 1 - i;
     LayerImpl* render_surface_layer = render_surface_layer_list[surface_index];
     RenderSurfaceImpl* render_surface = render_surface_layer->render_surface();
     DCHECK(render_surface);
@@ skipping 151 matching lines @@
     debug_rects_.push_back(
         DebugRect(ANIMATION_BOUNDS_RECT_TYPE,
                   gfx::ToEnclosingRect(gfx::RectF(inflated_bounds.x(),
                                                   inflated_bounds.y(),
                                                   inflated_bounds.width(),
                                                   inflated_bounds.height()))));
   }
 }
 
 }  // namespace cc