cc: Add tests for DisplayListRasterSource.

cc/playback/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/playback/display_list_recording_source.h"
 
 #include <algorithm>
 
 #include "cc/base/histograms.h"
 #include "cc/base/region.h"
 #include "cc/layers/content_layer_client.h"
 #include "cc/playback/display_item_list.h"
 #include "cc/playback/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;
 
+#ifdef NDEBUG
+const bool kDefaultClearCanvasSetting = false;
+#else
+const bool kDefaultClearCanvasSetting = true;
+#endif
+
 DEFINE_SCOPED_UMA_HISTOGRAM_AREA_TIMER(
     ScopedDisplayListRecordingSourceUpdateTimer,
     "Compositing.DisplayListRecordingSource.UpdateUs",
     "Compositing.DisplayListRecordingSource.UpdateInvalidatedAreaPerMs");
 
 }  // namespace
 
 namespace cc {
 
 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),
+      clear_canvas_with_debug_color_(kDefaultClearCanvasSetting),
       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() {
 }
 
@@ skipping 58 matching lines @@
     default:
       // case RecordingSource::RECORD_WITH_SK_NULL_CANVAS should not be reached
       NOTREACHED();
   }
 
   int repeat_count = 1;
   if (slow_down_raster_scale_factor_for_debug_ > 1) {
     repeat_count = slow_down_raster_scale_factor_for_debug_;
     painting_control = ContentLayerClient::DISPLAY_LIST_CACHING_DISABLED;
   }
+
   for (int i = 0; i < repeat_count; ++i) {
     display_list_ = painter->PaintContentsToDisplayList(recorded_viewport_,
                                                         painting_control);
   }
 
   is_suitable_for_gpu_rasterization_ =
       display_list_->IsSuitableForGpuRasterization();
   DetermineIfSolidColor();
   display_list_->EmitTraceSnapshot();
   if (gather_pixel_refs_)
@@ skipping 60 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