Remove unused fields from //content.

gpu/ipc/service/gpu_memory_tracking.h

 // Copyright (c) 2012 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 GPU_IPC_SERVICE_GPU_MEMORY_TRACKING_H_
 #define GPU_IPC_SERVICE_GPU_MEMORY_TRACKING_H_
 
 #include <stdint.h>
 
 #include "base/process/process.h"
@@ skipping 22 matching lines @@
  private:
   friend class GpuMemoryManager;
 
   GpuMemoryTrackingGroup(base::ProcessId pid,
                          gles2::MemoryTracker* memory_tracker,
                          GpuMemoryManager* memory_manager);
 
   base::ProcessId pid_;
   uint64_t size_;
 
-  // Set and used only during the Manage function, to determine which
-  // non-surface clients should be hibernated.
-  bool hibernated_;
-
   gles2::MemoryTracker* memory_tracker_;
   GpuMemoryManager* memory_manager_;
 };
 
 }  // namespace gpu
 
 #endif  // GPU_IPC_SERVICE_GPU_MEMORY_TRACKING_H_