Schedule idle handler based on CPU usage.

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index e3fdac37a5c6174232a56b006338176ff29e7f88..efb71782667a1a39515ec807417f9f39bfde591b 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -43,6 +43,7 @@ class WebStorageEventDispatcher;
 }
 
 namespace base {
+class ProcessMetrics;
 class MessageLoopProxy;
 class Thread;
 namespace win {
@@ -108,11 +109,7 @@ class CONTENT_EXPORT RenderThreadImpl : public content::RenderThread,
   virtual void RegisterExtension(v8::Extension* extension) OVERRIDE;
   virtual bool IsRegisteredExtension(
       const std::string& v8_extension_name) const OVERRIDE;
-  virtual void ScheduleIdleHandler(int64 initial_delay_ms) OVERRIDE;
-  virtual void IdleHandler() OVERRIDE;
-  virtual int64 GetIdleNotificationDelayInMs() const OVERRIDE;
-  virtual void SetIdleNotificationDelayInMs(
-      int64 idle_notification_delay_in_ms) OVERRIDE;
+  virtual void ResetIdleTimer() OVERRIDE;
 #if defined(OS_WIN)
   virtual void PreCacheFont(const LOGFONT& log_font) OVERRIDE;
   virtual void ReleaseCachedFonts() OVERRIDE;
@@ -126,6 +123,8 @@ class CONTENT_EXPORT RenderThreadImpl : public content::RenderThread,
   void DoNotSuspendWebKitSharedTimer();
   void DoNotNotifyWebKitOfModalLoop();
 
+  void IdleHandler();
+
   // Will be NULL if threaded compositing has not been enabled.
   CompositorThread* compositor_thread() const {
     return compositor_thread_.get();
@@ -184,6 +183,8 @@ class CONTENT_EXPORT RenderThreadImpl : public content::RenderThread,
   void OnGetAccessibilityTree();
   void OnTempCrashWithData(const GURL& data);
 
+  void ScheduleIdleHandler(int64 delay_ms);
+
   // These objects live solely on the render thread.
   scoped_ptr<ScopedRunnableMethodFactory<RenderThreadImpl> > task_factory_;
   scoped_ptr<AppCacheDispatcher> appcache_dispatcher_;
@@ -216,14 +217,16 @@ class CONTENT_EXPORT RenderThreadImpl : public content::RenderThread,
   int hidden_widget_count_;
 
   // The current value of the idle notification timer delay.
-  int64 idle_notification_delay_in_ms_;
+  int64 idle_delay_ms_;
+
+  // Timer that checks CPU usage and calls IdleHandler.
+  base::OneShotTimer<RenderThreadImpl> idle_timer_;
+
+  scoped_ptr<base::ProcessMetrics> process_metrics_;
 
   bool suspend_webkit_shared_timer_;
   bool notify_webkit_of_modal_loop_;
 
-  // Timer that periodically calls IdleHandler.
-  base::RepeatingTimer<RenderThreadImpl> idle_timer_;
-
   // The channel from the renderer process to the GPU process.
   scoped_refptr<GpuChannelHost> gpu_channel_;