Separated alt-tab window cycle from overview mode

ash/shell.h

Index: ash/shell.h
diff --git a/ash/shell.h b/ash/shell.h
index 718a6c6df431fdbbae62b597ce4ee7e73b9a8b3f..c53185aea943913426a6947a8d08a465ae004394 100644
--- a/ash/shell.h
+++ b/ash/shell.h
@@ -363,6 +363,9 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   VideoDetector* video_detector() {
     return video_detector_.get();
   }
+  WindowCycleController* window_cycle_controller() {
+    return window_cycle_controller_.get();
+  }
   WindowSelectorController* window_selector_controller() {
     return window_selector_controller_.get();
   }
@@ -644,6 +647,7 @@ class ASH_EXPORT Shell : public SystemModalContainerEventFilterDelegate,
   scoped_ptr<MruWindowTracker> mru_window_tracker_;
   scoped_ptr< ::wm::UserActivityDetector> user_activity_detector_;
   scoped_ptr<VideoDetector> video_detector_;
+  scoped_ptr<WindowCycleController> window_cycle_controller_;
   scoped_ptr<WindowSelectorController> window_selector_controller_;
   scoped_ptr<FocusCycler> focus_cycler_;
   scoped_ptr<DisplayController> display_controller_;