Purge memory before suspending timer queues when backgrounded.

content/renderer/render_thread_impl.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 CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 499 matching lines @@
   void OnChannelError() override;
 
   // ChildThread
   bool OnControlMessageReceived(const IPC::Message& msg) override;
   void OnProcessBackgrounded(bool backgrounded) override;
   void OnProcessResume() override;
   void OnProcessPurgeAndSuspend() override;
   void RecordAction(const base::UserMetricsAction& action) override;
   void RecordComputedAction(const std::string& action) override;
 
+  void PurgeBeforeSuspendTimerQueueWhenBackgrounded();
+  void SuspendTimerQueueWhenBackgrounded();
+
   bool IsMainThread();
 
   // base::MemoryCoordinatorClient implementation:
   void OnMemoryStateChange(base::MemoryState state) override;
 
   void ClearMemory();
 
   void Init(
       const scoped_refptr<base::SingleThreadTaskRunner>& resource_task_queue);
 
@@ skipping 226 matching lines @@
 
   AssociatedInterfaceRegistryImpl associated_interfaces_;
 
   mojo::AssociatedBinding<mojom::Renderer> renderer_binding_;
 
   mojom::RenderFrameMessageFilterAssociatedPtr render_frame_message_filter_;
   mojom::RenderMessageFilterAssociatedPtr render_message_filter_;
   scoped_refptr<mojom::ThreadSafeRenderMessageFilterAssociatedPtr>
       thread_safe_render_message_filter_;
 
+  // The amount of time to wait before suspending shared timers after the
+  // renderer has been backgrounded. This is used only if background suspension
+  // of shared timers is enabled.
+  static const int kSuspendTimersWhenBackgroundedDelayMillis = 5 * 60 * 1000;
+
+  base::CancelableClosure purge_before_suspend_timers_closure_;
+  base::CancelableClosure suspend_timers_when_backgrounded_closure_;
+
   base::CancelableClosure record_purge_suspend_metric_closure_;
   RendererMemoryMetrics purge_and_suspend_memory_metrics_;
   base::CancelableClosure record_purge_suspend_growth_metric_closure_;
 
   int32_t client_id_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 #if defined(COMPILER_MSVC)
 #pragma warning(pop)
 #endif
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_