[Extensions UI Mac] Fix a bug with popped out actions' highlighted state

chrome/browser/ui/cocoa/extensions/browser_action_button.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 CHROME_BROWSER_UI_COCOA_EXTENSIONS_BROWSER_ACTION_BUTTON_H_
 #define CHROME_BROWSER_UI_COCOA_EXTENSIONS_BROWSER_ACTION_BUTTON_H_
 
 #import <Cocoa/Cocoa.h>
 
 #include <memory>
@@ skipping 82 matching lines @@
 
 @property(readonly, nonatomic) BOOL isBeingDragged;
 
 @end
 
 @interface BrowserActionButton(TestingAPI)
 // Sets a context menu to use for testing purposes.
 - (void)setTestContextMenu:(NSMenu*)testContextMenu;
 // Returns true if the action wants to run.
 - (BOOL)wantsToRunForTesting;
+// Returns true if the cell is highlighted.
+- (BOOL)isHighlighted;
 @end
 
 @interface BrowserActionCell : ImageButtonCell {
  @private
   // The controller for the browser actions bar that owns the button. Weak.
   BrowserActionsController* browserActionsController_;
 }
 
 @property(assign, nonatomic)
     BrowserActionsController* browserActionsController;
 
 @end
 
 #endif  // CHROME_BROWSER_UI_COCOA_EXTENSIONS_BROWSER_ACTION_BUTTON_H_