convert //gpu to std::unique_ptr

cc/test/test_gpu_memory_buffer_manager.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_TEST_TEST_GPU_MEMORY_BUFFER_MANAGER_H_
 #define CC_TEST_TEST_GPU_MEMORY_BUFFER_MANAGER_H_
 
+#include <memory>
+
 #include "base/macros.h"
 #include "gpu/command_buffer/client/gpu_memory_buffer_manager.h"
 
 namespace cc {
 
 class TestGpuMemoryBufferManager : public gpu::GpuMemoryBufferManager {
  public:
   TestGpuMemoryBufferManager();
   ~TestGpuMemoryBufferManager() override;
 
@@ skipping 16 matching lines @@
   void SetDestructionSyncToken(gfx::GpuMemoryBuffer* buffer,
                                const gpu::SyncToken& sync_token) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TestGpuMemoryBufferManager);
 };
 
 }  // namespace cc
 
 #endif  // CC_TEST_TEST_GPU_MEMORY_BUFFER_MANAGER_H_