Introduce MemoryCoordinatorProxy in base

content/browser/browser_main_loop.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 "content/browser/browser_main_loop.h"
 
 #include <stddef.h>
 
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/feature_list.h"
 #include "base/location.h"
 #include "base/logging.h"
 #include "base/macros.h"
+#include "base/memory/memory_coordinator_proxy.h"
 #include "base/memory/memory_pressure_monitor.h"
 #include "base/memory/ptr_util.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/metrics/user_metrics.h"
 #include "base/pending_task.h"
 #include "base/power_monitor/power_monitor.h"
 #include "base/power_monitor/power_monitor_device_source.h"
 #include "base/process/process_metrics.h"
 #include "base/run_loop.h"
@@ skipping 1357 matching lines @@
 
 bool BrowserMainLoop::UsingInProcessGpu() const {
   return parsed_command_line_.HasSwitch(switches::kSingleProcess) ||
          parsed_command_line_.HasSwitch(switches::kInProcessGPU);
 }
 
 void BrowserMainLoop::InitializeMemoryManagementComponent() {
   if (base::FeatureList::IsEnabled(features::kMemoryCoordinator)) {
     // Disable MemoryPressureListener when memory coordinator is enabled.
     base::MemoryPressureListener::SetNotificationsSuppressed(true);
+    base::MemoryCoordinatorProxy::GetInstance()->
+        SetGetCurrentMemoryStateCallback(base::Bind(
+            &MemoryCoordinator::GetCurrentMemoryState,
+            base::Unretained(MemoryCoordinator::GetInstance())));

[danakj, 2016/10/21 18:56:30]

Can you leave a comment explaining why Unretained is safe here.

[hajimehoshi, 2016/10/24 06:51:06]

Done.

     return;
   }
 
   // TODO(chrisha): Abstract away this construction mess to a helper function,
   // once MemoryPressureMonitor is made a concrete class.
 #if defined(OS_CHROMEOS)
   if (chromeos::switches::MemoryPressureHandlingEnabled()) {
     memory_pressure_monitor_.reset(new base::chromeos::MemoryPressureMonitor(
         chromeos::switches::GetMemoryPressureThresholds()));
   }
@@ skipping 175 matching lines @@
     scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner =
         audio_thread_->task_runner();
     audio_manager_ = media::AudioManager::Create(std::move(audio_task_runner),
                                                  std::move(worker_task_runner),
                                                  MediaInternals::GetInstance());
   }
   CHECK(audio_manager_);
 }
 
 }  // namespace content