Allow canvases to be GPU-accelerated in Workers

third_party/WebKit/Source/platform/graphics/StaticBitmapImage.h

 // 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.
 
 #ifndef StaticBitmapImage_h
 #define StaticBitmapImage_h
 
 #include "platform/graphics/Image.h"
 #include "third_party/khronos/GLES2/gl2.h"
 #include "third_party/skia/include/core/SkRefCnt.h"
@@ skipping 16 matching lines @@
 
     sk_sp<SkImage> imageForCurrentFrame() override;
 
     bool originClean() const { return m_isOriginClean; }
     void setOriginClean(bool flag) { m_isOriginClean = flag; }
     bool isPremultiplied() const { return m_isPremultiplied; }
     void setPremultiplied(bool flag) { m_isPremultiplied = flag; }
     bool isTextureBacked() override;
     virtual void copyToTexture(WebGraphicsContext3DProvider*, GLuint, GLenum, GLenum, bool) { NOTREACHED(); }
     virtual bool hasMailbox() { return false; }
+    virtual void transfer() { }
 
 protected:
     StaticBitmapImage(sk_sp<SkImage>);
     StaticBitmapImage() { } // empty constructor for derived class.
     sk_sp<SkImage> m_image;
 
 private:
     bool m_isOriginClean = true;
     // The premultiply info is stored here because the SkImage API
     // doesn't expose this info.
     bool m_isPremultiplied = true;
 };
 
 } // namespace blink
 
 #endif