Open the WrenchMenu on mouseover when dragging a browser action

chrome/browser/ui/views/toolbar/extension_toolbar_menu_view.h

 // Copyright 2014 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 CHROME_BROWSER_UI_VIEWS_TOOLBAR_EXTENSION_TOOLBAR_MENU_VIEW_H_
 #define CHROME_BROWSER_UI_VIEWS_TOOLBAR_EXTENSION_TOOLBAR_MENU_VIEW_H_
 
+#include "base/memory/weak_ptr.h"
+#include "base/scoped_observer.h"
+#include "chrome/browser/ui/views/toolbar/browser_actions_container_observer.h"
 #include "ui/views/view.h"
 
 class Browser;
 class BrowserActionsContainer;
+class WrenchMenu;
 
 // ExtensionToolbarMenuView is the view containing the extension actions that
 // overflowed from the BrowserActionsContainer, and is contained in and owned by
 // the wrench menu.
-class ExtensionToolbarMenuView : public views::View {
+// In the event that the WrenchMenu was opened for an Extension Action drag-and-
+// drop, this will also close the menu upon completion.
+class ExtensionToolbarMenuView : public views::View,
+                                 public BrowserActionsContainerObserver {
  public:
-  explicit ExtensionToolbarMenuView(Browser* browser);
+  ExtensionToolbarMenuView(Browser* browser, WrenchMenu* wrench_menu);
   virtual ~ExtensionToolbarMenuView();
 
   // views::View:
   virtual gfx::Size GetPreferredSize() const OVERRIDE;
   virtual void Layout() OVERRIDE;
 
  private:
+  // BrowserActionsContainerObserver:
+  virtual void OnBrowserActionDragDone() OVERRIDE;
+
+  // The associated browser.
   Browser* browser_;
+
+  // The WrenchMenu, which may need to be closed after a drag-and-drop.
+  WrenchMenu* wrench_menu_;
+
+  // The overflow BrowserActionsContainer which is nested in this view.
   BrowserActionsContainer* container_;
 
+  ScopedObserver<BrowserActionsContainer, BrowserActionsContainerObserver>
+      browser_actions_container_observer_;
+
   DISALLOW_COPY_AND_ASSIGN(ExtensionToolbarMenuView);
 };
 
 #endif  // CHROME_BROWSER_UI_VIEWS_TOOLBAR_EXTENSION_TOOLBAR_MENU_VIEW_H_