Use DiscardableMemoryManager on Android.

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_MALLOC_H_
-#define BASE_MEMORY_DISCARDABLE_MEMORY_MALLOC_H_
+#ifndef BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_
+#define BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_
 
 #include "base/memory/discardable_memory.h"
 
+#include "base/basictypes.h"
+#include "base/compiler_specific.h"
+#include "base/memory/discardable_memory_manager.h"
+
 namespace base {
 namespace internal {
 
-class DiscardableMemoryMalloc : public DiscardableMemory {
+class DiscardableMemoryAshmem : public DiscardableMemory {
  public:
-  explicit DiscardableMemoryMalloc(size_t size);
-  virtual ~DiscardableMemoryMalloc();
+  DiscardableMemoryAshmem(DiscardableMemoryManager* manager, size_t size);
+  virtual ~DiscardableMemoryAshmem();
 
   bool Initialize();
 
-  // Overridden from DiscardableMemory:
+  // DiscardableMemory:
   virtual DiscardableMemoryLockStatus Lock() OVERRIDE;
   virtual void Unlock() OVERRIDE;
   virtual void* Memory() const OVERRIDE;
 
  private:
-  scoped_ptr<uint8, FreeDeleter> memory_;
-  const size_t size_;
+  DiscardableMemoryManager* const manager_;
+  const DiscardableMemoryManager::AllocationId allocation_id_;
+  void* memory_;
 
-  DISALLOW_COPY_AND_ASSIGN(DiscardableMemoryMalloc);
+  DISALLOW_COPY_AND_ASSIGN(DiscardableMemoryAshmem);
 };
 
 }  // namespace internal
 }  // namespace base
 
-#endif  // BASE_MEMORY_DISCARDABLE_MEMORY_MALLOC_H_
+#endif  // BASE_MEMORY_DISCARDABLE_MEMORY_ASHMEM_H_