Enable disabling WebCore::GraphicsContext in telemetry.

cc/resources/picture.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/resources/picture.h"
 
 #include <algorithm>
 #include <limits>
 #include <set>
 
@@ skipping 243 matching lines @@
   SkTileGridFactory factory(tile_grid_info);
   SkPictureRecorder recorder;
 
   skia::RefPtr<SkCanvas> canvas;
   canvas = skia::SharePtr(
       recorder.beginRecording(layer_rect_.width(),
                               layer_rect_.height(),
                               &factory,
                               SkPicture::kUsePathBoundsForClip_RecordingFlag));
 
+  bool disableGraphicsContext = false;

[Sami, 2014/04/29 10:57:23]

hacker_style here too.

[Stephen Chennney, 2014/04/29 20:30:45]

Done.

+
   switch (recording_mode) {
     case RECORD_NORMALLY:
       // Already setup for normal recording
       break;
     case RECORD_WITH_SK_NULL_CANVAS:
       canvas = skia::AdoptRef(SkCreateNullCanvas());
       break;
     case RECORD_WITH_PAINTING_DISABLED:
-      // Blink's GraphicsContext will disable painting when given a NULL
-      // canvas.
-      canvas.clear();
+      // We pass a disable flag through the paint calls

[Sami, 2014/04/29 10:57:23]

nit: end comments with punctuation.

[Stephen Chennney, 2014/04/29 20:30:45]

Done.

+      disableGraphicsContext = true;
       break;
     default:
       NOTREACHED();
   }
 
   if (canvas) {
     canvas->save();
     canvas->translate(SkFloatToScalar(-layer_rect_.x()),
                       SkFloatToScalar(-layer_rect_.y()));
 
     SkRect layer_skrect = SkRect::MakeXYWH(layer_rect_.x(),
                                            layer_rect_.y(),
                                            layer_rect_.width(),
                                            layer_rect_.height());
     canvas->clipRect(layer_skrect);
   }
 
   gfx::RectF opaque_layer_rect;
-  painter->PaintContents(canvas.get(), layer_rect_, &opaque_layer_rect);
+  painter->PaintContents(
+      canvas.get(), layer_rect_, &opaque_layer_rect, disableGraphicsContext);
 
   if (canvas)
     canvas->restore();
   picture_ = skia::AdoptRef(recorder.endRecording());
   DCHECK(picture_);
 
   opaque_rect_ = gfx::ToEnclosedRect(opaque_layer_rect);
 
   EmitTraceSnapshot();
 }
@@ skipping 241 matching lines @@
 
 scoped_refptr<base::debug::ConvertableToTraceFormat>
     Picture::AsTraceableRecordData() const {
   scoped_ptr<base::DictionaryValue> record_data(new base::DictionaryValue());
   record_data->Set("picture_id", TracedValue::CreateIDRef(this).release());
   record_data->Set("layer_rect", MathUtil::AsValue(layer_rect_).release());
   return TracedValue::FromValue(record_data.release());
 }
 
 }  // namespace cc