Revert 267170 "Use DiscardableMemoryManager on Android."

trunk/src/base/memory/discardable_memory_ashmem.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 BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_
-#define BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_
-
-#include "base/memory/discardable_memory.h"
-
-#include "base/macros.h"
-#include "base/memory/discardable_memory_manager.h"
-
-namespace base {
-namespace internal {
-
-class DiscardableAshmemChunk;
-class DiscardableMemoryAshmemAllocator;
-class DiscardableMemoryManager;
-
-class DiscardableMemoryAshmem
-    : public DiscardableMemory,
-      public internal::DiscardableMemoryManagerAllocation {
- public:
-  explicit DiscardableMemoryAshmem(size_t bytes,
-                                   DiscardableMemoryAshmemAllocator* allocator,
-                                   DiscardableMemoryManager* manager);
-
-  virtual ~DiscardableMemoryAshmem();
-
-  bool Initialize();
-
-  // Overridden from DiscardableMemory:
-  virtual DiscardableMemoryLockStatus Lock() OVERRIDE;
-  virtual void Unlock() OVERRIDE;
-  virtual void* Memory() const OVERRIDE;
-
-  // Overridden from internal::DiscardableMemoryManagerAllocation:
-  virtual bool AllocateAndAcquireLock() OVERRIDE;
-  virtual void ReleaseLock() OVERRIDE;
-  virtual void Purge() OVERRIDE;
-
- private:
-  const size_t bytes_;
-  DiscardableMemoryAshmemAllocator* const allocator_;
-  DiscardableMemoryManager* const manager_;
-  bool is_locked_;
-  scoped_ptr<DiscardableAshmemChunk> ashmem_chunk_;
-
-  DISALLOW_COPY_AND_ASSIGN(DiscardableMemoryAshmem);
-};
-
-}  // namespace internal
-}  // namespace base
-
-#endif  // BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_