Revert of Fix for menus blocking user activity detection (Retry).

extensions/shell/browser/shell_desktop_controller_aura.cc

Index: extensions/shell/browser/shell_desktop_controller_aura.cc
diff --git a/extensions/shell/browser/shell_desktop_controller_aura.cc b/extensions/shell/browser/shell_desktop_controller_aura.cc
index 32983bb403272941dbf6b4185ca02b6b34c92cc2..a3dcd6e79e9f17adfa5bc0c658e937e3a156f9fa 100644
--- a/extensions/shell/browser/shell_desktop_controller_aura.cc
+++ b/extensions/shell/browser/shell_desktop_controller_aura.cc
@@ -279,6 +279,8 @@
   aura::client::SetCursorClient(host_->window(), cursor_manager_.get());
 
   user_activity_detector_.reset(new ui::UserActivityDetector);
+  host_->event_processor()->GetRootTarget()->AddPreTargetHandler(
+      user_activity_detector_.get());
 #if defined(OS_CHROMEOS)
   user_activity_notifier_.reset(
       new ui::UserActivityPowerManagerNotifier(user_activity_detector_.get()));
@@ -322,6 +324,10 @@
   host_->RemoveObserver(this);
   if (input_method_filter_)
     root_window_event_filter_->RemoveHandler(input_method_filter_.get());
+  if (user_activity_detector_) {
+    host_->event_processor()->GetRootTarget()->RemovePreTargetHandler(
+        user_activity_detector_.get());
+  }
   wm::FocusController* focus_controller =
       static_cast<wm::FocusController*>(focus_client_.get());
   if (focus_controller) {