Remove unused fields from //content.

gpu/ipc/service/gpu_memory_tracking.cc

 // 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.
 
 #include "gpu/ipc/service/gpu_memory_tracking.h"
 
 #include "gpu/ipc/service/gpu_memory_manager.h"
 
 namespace gpu {
 
 GpuMemoryTrackingGroup::GpuMemoryTrackingGroup(
     base::ProcessId pid,
     gles2::MemoryTracker* memory_tracker,
     GpuMemoryManager* memory_manager)
     : pid_(pid),
       size_(0),
-      hibernated_(false),
       memory_tracker_(memory_tracker),
       memory_manager_(memory_manager) {
 }
 
 GpuMemoryTrackingGroup::~GpuMemoryTrackingGroup() {
   memory_manager_->OnDestroyTrackingGroup(this);
 }
 
 void GpuMemoryTrackingGroup::TrackMemoryAllocatedChange(uint64_t old_size,
                                                         uint64_t new_size) {
   memory_manager_->TrackMemoryAllocatedChange(
       this, old_size, new_size);
 }
 
 bool GpuMemoryTrackingGroup::EnsureGPUMemoryAvailable(uint64_t size_needed) {
   return memory_manager_->EnsureGPUMemoryAvailable(size_needed);
 }
 
 
 }  // namespace gpu