don't create SkDevice directly, use SkBitmap or (better) SkCanvas::NewRaster factory

cc/resources/resource_provider.cc

Index: cc/resources/resource_provider.cc
diff --git a/cc/resources/resource_provider.cc b/cc/resources/resource_provider.cc
index e58ed0b73b7c33c01b62ae654d8ec3bdf1664704..c751e7c545e7a9145b9e0407e6fac17f53cb1420 100644
--- a/cc/resources/resource_provider.cc
+++ b/cc/resources/resource_provider.cc
@@ -497,9 +497,7 @@ SkCanvas* ResourceProvider::BitmapRasterBuffer::DoLockForWrite() {
       NOTREACHED();
       break;
   }
-  skia::RefPtr<SkBitmapDevice> device =
-      skia::AdoptRef(new SkBitmapDevice(raster_bitmap_));
-  raster_canvas_ = skia::AdoptRef(new SkCanvas(device.get()));
+  raster_canvas_ = skia::AdoptRef(new SkCanvas(raster_bitmap_));
   raster_bitmap_generation_id_ = raster_bitmap_.getGenerationID();
   return raster_canvas_.get();
 }