Match html canvas which is transferred to OffscreenCanvas to CSS style

third_party/WebKit/Source/platform/graphics/CanvasSurfaceLayerBridge.cpp

 // Copyright 2016 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 "platform/graphics/CanvasSurfaceLayerBridge.h"
 
 #include "cc/layers/surface_layer.h"
 #include "cc/surfaces/surface_id.h"
 #include "cc/surfaces/surface_sequence.h"
 #include "platform/graphics/GraphicsLayer.h"
@@ skipping 19 matching lines @@
 
   cc::SurfaceLayer::SatisfyCallback satisfyCallback =
       convertToBaseCallback(WTF::bind(
           &CanvasSurfaceLayerBridge::satisfyCallback, WTF::unretained(this)));
   cc::SurfaceLayer::RequireCallback requireCallback =
       convertToBaseCallback(WTF::bind(
           &CanvasSurfaceLayerBridge::requireCallback, WTF::unretained(this)));
   m_surfaceLayer = cc::SurfaceLayer::Create(std::move(satisfyCallback),
                                             std::move(requireCallback));
   m_surfaceLayer->SetSurfaceId(m_surfaceId, 1.f,
-                               gfx::Size(canvasWidth, canvasHeight));
+                               gfx::Size(canvasWidth, canvasHeight),
+                               true /* scale layer bounds with surface size */);
 
   m_webLayer = Platform::current()->compositorSupport()->createLayerFromCCLayer(
       m_surfaceLayer.get());
   GraphicsLayer::registerContentsLayer(m_webLayer.get());
   return true;
 }
 
 void CanvasSurfaceLayerBridge::satisfyCallback(
     const cc::SurfaceSequence& sequence) {
   m_service->Satisfy(sequence);
 }
 
 void CanvasSurfaceLayerBridge::requireCallback(
     const cc::SurfaceId& surfaceId,
     const cc::SurfaceSequence& sequence) {
   m_service->Require(surfaceId, sequence);
 }
 
 }  // namespace blink