Change behaviour of the Alt-] and Alt-[ keys so that it cycles through SnapLeft/SnapRight to DockLe…

ash/wm/panels/panel_layout_manager.h

Index: ash/wm/panels/panel_layout_manager.h
diff --git a/ash/wm/panels/panel_layout_manager.h b/ash/wm/panels/panel_layout_manager.h
index 494d2c2ad0951e7b5468e9ba70f5e677c7acacaf..b5925006db9df019855a34a6ab2e17b238fe134d 100644
--- a/ash/wm/panels/panel_layout_manager.h
+++ b/ash/wm/panels/panel_layout_manager.h
@@ -103,6 +103,10 @@ class ASH_EXPORT PanelLayoutManager
                                        intptr_t old) OVERRIDE;
 
   // Overridden from ash::wm::WindowStateObserver
+  virtual void OnPreWindowStateTypeChange(
+      wm::WindowState* window_state,
+      wm::WindowStateType old_type) OVERRIDE;
+
   virtual void OnPostWindowStateTypeChange(
       wm::WindowState* window_state,
       wm::WindowStateType old_type) OVERRIDE;