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

ui/views/controls/menu/menu_controller.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_
 #define UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_
 
 #include "build/build_config.h"
 
 #include <list>
@@ skipping 74 matching lines @@
                     MenuAnchorPosition position,
                     bool context_menu,
                     int* event_flags);
 
   // Whether or not Run blocks.
   bool IsBlockingRun() const { return blocking_run_; }
 
   // Whether or not drag operation is in progress.
   bool drag_in_progress() const { return drag_in_progress_; }
 
+  // Since general Views and MenuItemViews have different mechanisms for
+  // implementing drag, it is possible that a child view will want to use
+  // its own dragging, in which case it needs to notify the controller that
+  // a drag is in progress to avoid closing the active menu.
+  void set_drag_in_progress(bool drag_in_progress) {
+    drag_in_progress_ = drag_in_progress;
+  }
+
   // Returns the owner of child windows.
   // WARNING: this may be NULL.
   Widget* owner() { return owner_; }
 
   // Get the anchor position wich is used to show this menu.
   MenuAnchorPosition GetAnchorPosition() { return state_.anchor; }
 
   // Cancels the current Run. See ExitType for a description of what happens
   // with the various parameters.
   void Cancel(ExitType type);
@@ skipping 499 matching lines @@
   bool item_selected_by_touch_;
 
   scoped_ptr<MenuMessageLoop> message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(MenuController);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_MENU_MENU_CONTROLLER_H_