Make DrawingBuffer and Canvas2DLayerBridge be cc::TextureLayerClients.

cc/blink/web_external_bitmap_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 CC_BLINK_WEB_EXTERNAL_BITMAP_IMPL_H_
-#define CC_BLINK_WEB_EXTERNAL_BITMAP_IMPL_H_
-
-#include <stdint.h>
-
-#include <memory>
-
-#include "base/bind.h"
-#include "base/macros.h"
-#include "cc/blink/cc_blink_export.h"
-#include "third_party/WebKit/public/platform/WebExternalBitmap.h"
-
-namespace cc {
-class SharedBitmap;
-}
-
-namespace cc_blink {
-
-typedef std::unique_ptr<cc::SharedBitmap> (*SharedBitmapAllocationFunction)(
-    const gfx::Size& size);
-
-// Sets the function that this will use to allocate shared memory.
-CC_BLINK_EXPORT void SetSharedBitmapAllocationFunction(
-    SharedBitmapAllocationFunction);
-
-class WebExternalBitmapImpl : public blink::WebExternalBitmap {
- public:
-  CC_BLINK_EXPORT explicit WebExternalBitmapImpl();
-  virtual ~WebExternalBitmapImpl();
-
-  // blink::WebExternalBitmap implementation.
-  blink::WebSize size() override;
-  void setSize(blink::WebSize size) override;
-  uint8_t* pixels() override;
-
-  cc::SharedBitmap* shared_bitmap() { return shared_bitmap_.get(); }
-
- private:
-  std::unique_ptr<cc::SharedBitmap> shared_bitmap_;
-  blink::WebSize size_;
-
-  DISALLOW_COPY_AND_ASSIGN(WebExternalBitmapImpl);
-};
-
-}  // namespace cc_blink
-
-#endif  // CC_BLINK_WEB_EXTERNAL_BITMAP_IMPL_H_