| Index: ash/frame/caption_buttons/frame_size_button.cc | 
| diff --git a/ash/frame/caption_buttons/frame_size_button.cc b/ash/frame/caption_buttons/frame_size_button.cc | 
| index 1399453ffdcfff07c8b357fc88001905a58fac16..05579bd13cf219b90d6b574cb7e13ec1fe1e040c 100644 | 
| --- a/ash/frame/caption_buttons/frame_size_button.cc | 
| +++ b/ash/frame/caption_buttons/frame_size_button.cc | 
| @@ -214,6 +214,7 @@ void FrameSizeButton::UpdateSnapType(const ui::LocatedEvent& event) { | 
| case CAPTION_BUTTON_ICON_MAXIMIZE_RESTORE: | 
| case CAPTION_BUTTON_ICON_MINIMIZE: | 
| case CAPTION_BUTTON_ICON_CLOSE: | 
| +      case CAPTION_BUTTON_ICON_BACK: | 
| case CAPTION_BUTTON_ICON_COUNT: | 
| NOTREACHED(); | 
| break; | 
|  |