Update some uses of char16 to use the base:: namespace.

ui/views/controls/menu/menu_controller.h

Index: ui/views/controls/menu/menu_controller.h
diff --git a/ui/views/controls/menu/menu_controller.h b/ui/views/controls/menu/menu_controller.h
index 1404d54e5d61166d92a30ac4d847b761f42be412..6dc77feddc6710fb020b56a48f3143111a01e846 100644
--- a/ui/views/controls/menu/menu_controller.h
+++ b/ui/views/controls/menu/menu_controller.h
@@ -416,8 +416,8 @@ class VIEWS_EXPORT MenuController : public base::MessageLoop::Dispatcher,
   // |match_function| is used to determine which menus match.
   SelectByCharDetails FindChildForMnemonic(
       MenuItemView* parent,
-      char16 key,
-      bool (*match_function)(MenuItemView* menu, char16 mnemonic));
+      base::char16 key,
+      bool (*match_function)(MenuItemView* menu, base::char16 mnemonic));
 
   // Selects or accepts the appropriate menu item based on |details|. Returns
   // true if |Accept| was invoked (which happens if there aren't multiple item
@@ -426,7 +426,7 @@ class VIEWS_EXPORT MenuController : public base::MessageLoop::Dispatcher,
 
   // Selects by mnemonic, and if that doesn't work tries the first character of
   // the title. Returns true if a match was selected and the menu should exit.
-  bool SelectByChar(char16 key);
+  bool SelectByChar(base::char16 key);
 
   // For Windows and Aura we repost an event for some events that dismiss
   // the context menu. The event is then reprocessed to cause its result