[ash-md] Fades overview header in and out

ash/common/wm/overview/overview_animation_type.h

Index: ash/common/wm/overview/overview_animation_type.h
diff --git a/ash/common/wm/overview/overview_animation_type.h b/ash/common/wm/overview/overview_animation_type.h
index 5db93566192ae92517a61d5fa8244ce9625bcb07..1df0b4119ecd29bdd3eccf39bd04d6f9a1e39cf4 100644
--- a/ash/common/wm/overview/overview_animation_type.h
+++ b/ash/common/wm/overview/overview_animation_type.h
@@ -14,6 +14,8 @@ enum OverviewAnimationType {
   OVERVIEW_ANIMATION_NONE,
   // Used to fade in the close button and label.
   OVERVIEW_ANIMATION_ENTER_OVERVIEW_MODE_FADE_IN,
+  // Used to fade in the header after transform animation is complete.
+  OVERVIEW_ANIMATION_FADE_IN_HEADER,
   // Used to position windows when entering/exiting overview mode and when a
   // window is closed while overview mode is active.
   OVERVIEW_ANIMATION_LAY_OUT_SELECTOR_ITEMS,