allocator cleanup: remove memory benchmarking extension

content/browser/renderer_host/memory_benchmark_message_filter.h

-// Copyright (c) 2013 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_BROWSER_RENDERER_HOST_MEMORY_BENCHMARK_MESSAGE_FILTER_H_
-#define CONTENT_BROWSER_RENDERER_HOST_MEMORY_BENCHMARK_MESSAGE_FILTER_H_
-
-#include <string>
-
-#include "base/macros.h"
-#include "content/public/browser/browser_message_filter.h"
-
-namespace content {
-
-class MemoryBenchmarkMessageFilter : public BrowserMessageFilter {
- public:
-  MemoryBenchmarkMessageFilter();
-
-  bool OnMessageReceived(const IPC::Message& message) override;
-
- private:
-  ~MemoryBenchmarkMessageFilter() override;
-
-  void OnHeapProfilerDump(const std::string& reason);
-
-  DISALLOW_COPY_AND_ASSIGN(MemoryBenchmarkMessageFilter);
-};
-
-}  // namespace content
-
-#endif  // CONTENT_BROWSER_RENDERER_HOST_MEMORY_BENCHMARK_MESSAGE_FILTER_H_