Revert of Revert of Implement DisplayList GatherPixelRefs

cc/resources/display_list_recording_source.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/resources/display_list_recording_source.h"
 
 #include <algorithm>
 
 #include "cc/base/region.h"
 #include "cc/layers/content_layer_client.h"
 #include "cc/resources/display_item_list.h"
 #include "cc/resources/display_list_raster_source.h"
 #include "skia/ext/analysis_canvas.h"
 
 namespace {
 
 // Layout pixel buffer around the visible layer rect to record.  Any base
 // picture that intersects the visible layer rect expanded by this distance
 // will be recorded.
 const int kPixelDistanceToRecord = 8000;
 // We don't perform solid color analysis on images that have more than 10 skia
 // operations.
 const int kOpCountThatIsOkToAnalyze = 10;
 
 }  // namespace
 
 namespace cc {
 
-DisplayListRecordingSource::DisplayListRecordingSource()
+DisplayListRecordingSource::DisplayListRecordingSource(
+    const gfx::Size& grid_cell_size)
     : slow_down_raster_scale_factor_for_debug_(0),
       gather_pixel_refs_(false),
       requires_clear_(false),
       is_solid_color_(false),
       solid_color_(SK_ColorTRANSPARENT),
       background_color_(SK_ColorTRANSPARENT),
       pixel_record_distance_(kPixelDistanceToRecord),
+      grid_cell_size_(grid_cell_size),
       is_suitable_for_gpu_rasterization_(true) {
 }
 
 DisplayListRecordingSource::~DisplayListRecordingSource() {
 }
 
 bool DisplayListRecordingSource::UpdateAndExpandInvalidation(
     ContentLayerClient* painter,
     Region* invalidation,
     const gfx::Size& layer_size,
@@ skipping 61 matching lines @@
                                                         painting_control);
   }
   display_list_->set_layer_rect(recorded_viewport_);
   is_suitable_for_gpu_rasterization_ =
       display_list_->IsSuitableForGpuRasterization();
 
   DetermineIfSolidColor();
   display_list_->EmitTraceSnapshot();
 
   display_list_->CreateAndCacheSkPicture();
+  if (gather_pixel_refs_)
+    display_list_->GatherPixelRefs(grid_cell_size_);
 
   return true;
 }
 
 void DisplayListRecordingSource::DidMoveToNewCompositor() {
   // No invalidation history to worry about here.
 }
 
 gfx::Size DisplayListRecordingSource::GetSize() const {
   return size_;
@@ skipping 53 matching lines @@
   is_solid_color_ = canvas.GetColorIfSolid(&solid_color_);
 }
 
 void DisplayListRecordingSource::Clear() {
   recorded_viewport_ = gfx::Rect();
   display_list_ = NULL;
   is_solid_color_ = false;
 }
 
 }  // namespace cc