Schedule idle handler in the foreground tab based on CPU usage and user activity.

content/renderer/render_view_impl.cc

Index: content/renderer/render_view_impl.cc
diff --git a/content/renderer/render_view_impl.cc b/content/renderer/render_view_impl.cc
index 50ecbff876e2b8f47a833cf4c7f731fea794d1d1..6f905cd154d41d40fe73f9891e78e414fb7d58ca 100644
--- a/content/renderer/render_view_impl.cc
+++ b/content/renderer/render_view_impl.cc
@@ -50,6 +50,7 @@
 #include "content/renderer/external_popup_menu.h"
 #include "content/renderer/geolocation_dispatcher.h"
 #include "content/renderer/gpu/webgraphicscontext3d_command_buffer_impl.h"
+#include "content/renderer/idle_user_detector.h"
 #include "content/renderer/intents_dispatcher.h"
 #include "content/renderer/java/java_bridge_dispatcher.h"
 #include "content/renderer/load_progress_tracker.h"
@@ -407,6 +408,8 @@ RenderViewImpl::RenderViewImpl(
 
   renderer_accessibility_ = new RendererAccessibility(this);
 
+  new IdleUserDetector(this);
+
   const CommandLine& command_line = *CommandLine::ForCurrentProcess();
   if (command_line.HasSwitch(switches::kEnableMediaStream)) {
     media_stream_impl_ = new MediaStreamImpl(