Implement offscreenCanvas.getContext('webgl') on a worker thread

content/renderer/webgraphicscontext3d_provider_impl.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 CONTENT_RENDERER_WEBGRAPHICSCONTEXT3D_PROVIDER_IMPL_H_
 #define CONTENT_RENDERER_WEBGRAPHICSCONTEXT3D_PROVIDER_IMPL_H_
 
 #include "base/compiler_specific.h"
 #include "base/memory/ref_counted.h"
 #include "content/common/content_export.h"
@@ skipping 20 matching lines @@
   GrContext* grContext() override;
   gpu::Capabilities getCapabilities() override;
   void setLostContextCallback(blink::WebClosure) override;
   void setErrorMessageCallback(
       blink::WebFunction<void(const char*, int32_t)>) override;
 
   ContextProviderCommandBuffer* context_provider() const {
     return provider_.get();
   }
 
+  bool bindToCurrentThread() override;
+
  private:
   scoped_refptr<ContextProviderCommandBuffer> provider_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_WEBGRAPHICSCONTEXT3D_PROVIDER_IMPL_H_