Enable disabling WebCore::GraphicsContext in telemetry.

cc/resources/picture.cc

Index: cc/resources/picture.cc
diff --git a/cc/resources/picture.cc b/cc/resources/picture.cc
index 48f03e0ba842a864975eef07cb8e19cf2988db4f..d9e2931536014664edf83d9021cc527ac58b25dd 100644
--- a/cc/resources/picture.cc
+++ b/cc/resources/picture.cc
@@ -261,6 +261,8 @@ void Picture::Record(ContentLayerClient* painter,
                               &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
@@ -269,9 +271,8 @@ void Picture::Record(ContentLayerClient* painter,
       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();
@@ -290,7 +291,8 @@ void Picture::Record(ContentLayerClient* painter,
   }
 
   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();