Allow menus to stay open during a child view's drag and drop

ui/views/controls/menu/menu_delegate.h

Index: ui/views/controls/menu/menu_delegate.h
diff --git a/ui/views/controls/menu/menu_delegate.h b/ui/views/controls/menu/menu_delegate.h
index 7f4b74fb53c4b679c0d2372f222b1349d48c8fde..5db3a555b496b03b038947e8c777fe51e552adb3 100644
--- a/ui/views/controls/menu/menu_delegate.h
+++ b/ui/views/controls/menu/menu_delegate.h
@@ -132,6 +132,10 @@ class VIEWS_EXPORT MenuDelegate {
   // context menu should be closed.
   virtual bool ShouldCloseAllMenusOnExecute(int id);
 
+  // Returns true if the menu should close upon a drag completing. Defaults to
+  // true.

[sky, 2014/07/14 15:19:05]

Document this is only invoked for menus originating outside of those on menu
items. Also, move this right above SelectionChanged() so that it's grouped with
the other dnd functions.

[Devlin, 2014/07/16 16:00:45]

Done.

+  virtual bool ShouldCloseOnDragComplete();
+
   // Executes the specified command. mouse_event_flags give the flags of the
   // mouse event that triggered this to be invoked (ui::MouseEvent
   // flags). mouse_event_flags is 0 if this is triggered by a user gesture