Replace blink::WebDiscardableMemory with base::DiscardableMemory.

content/child/web_discardable_memory_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_CHILD_WEB_DISCARDABLE_MEMORY_IMPL_H_
-#define CONTENT_CHILD_WEB_DISCARDABLE_MEMORY_IMPL_H_
-
-#include <stddef.h>
-
-#include "base/macros.h"
-#include "base/memory/scoped_ptr.h"
-#include "third_party/WebKit/public/platform/WebDiscardableMemory.h"
-
-namespace base {
-class DiscardableMemory;
-}
-
-namespace content {
-
-// Implementation of WebDiscardableMemory that is responsible for allocating
-// discardable memory.
-class WebDiscardableMemoryImpl : public blink::WebDiscardableMemory {
- public:
-  ~WebDiscardableMemoryImpl() override;
-
-  static scoped_ptr<WebDiscardableMemoryImpl> CreateLockedMemory(size_t size);
-
-  // blink::WebDiscardableMemory:
-  bool lock() override;
-  void unlock() override;
-  void* data() override;
-  blink::WebMemoryAllocatorDump* createMemoryAllocatorDump(
-      const blink::WebString& name,
-      blink::WebProcessMemoryDump* wpmd) const override;
-
- private:
-  WebDiscardableMemoryImpl(scoped_ptr<base::DiscardableMemory> memory);
-
-  scoped_ptr<base::DiscardableMemory> discardable_;
-
-  DISALLOW_COPY_AND_ASSIGN(WebDiscardableMemoryImpl);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_CHILD_WEB_DISCARDABLE_MEMORY_IMPL_H_