Eliminate ash::internal namespace

ash/system/tray/tray_item_view.h

Index: ash/system/tray/tray_item_view.h
diff --git a/ash/system/tray/tray_item_view.h b/ash/system/tray/tray_item_view.h
index 761e918791cead1c3e0ec262be2dd57dcafafb55..854af3c13e7a055510f6d87b0bdcdc0904136b84 100644
--- a/ash/system/tray/tray_item_view.h
+++ b/ash/system/tray/tray_item_view.h
@@ -19,11 +19,8 @@ class Label;
 }
 
 namespace ash {
-
 class SystemTrayItem;
 
-namespace internal {
-
 // Base-class for items in the tray. It makes sure the widget is updated
 // correctly when the visibility/size of the tray item changes. It also adds
 // animation when showing/hiding the item in the tray.
@@ -79,7 +76,6 @@ class ASH_EXPORT TrayItemView : public views::View,
   DISALLOW_COPY_AND_ASSIGN(TrayItemView);
 };
 
-}  // namespace internal
 }  // namespace ash
 
 #endif  // ASH_SYSTEM_TRAY_TRAY_ITEM_VIEW_H_