Ensure that a browser action is never passed to a function which expects a page action.

chrome/browser/cocoa/location_bar/location_bar_view_mac.h

 // Copyright (c) 2010 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_COCOA_LOCATION_BAR_VIEW_MAC_H_
 #define CHROME_BROWSER_COCOA_LOCATION_BAR_VIEW_MAC_H_
 #pragma once
 
 #include <string>
 
@@ skipping 92 matching lines @@
 
   // Sets preview_enabled_ for the PageActionImageView associated with this
   // |page_action|. If |preview_enabled|, the location bar will display the
   // PageAction icon even if it has not been activated by the extension.
   // This is used by the ExtensionInstalledBubble to preview what the icon
   // will look like for the user upon installation of the extension.
   void SetPreviewEnabledPageAction(ExtensionAction* page_action,
                                    bool preview_enabled);
 
   // Return |page_action|'s info-bubble point in window coordinates.
-  // Returns |NSZeroPoint| if |page_action| is not present.
+  // This function should always be called with a visible page action.
+  // If |page_action| is not a page action or not visible, NOTREACHED()
+  // is called and this function returns |NSZeroPoint|.
   NSPoint GetPageActionBubblePoint(ExtensionAction* page_action);
 
   // Get the blocked-popup content setting's frame in window
   // coordinates.  Used by the blocked-popup animation.  Returns
   // |NSZeroRect| if the relevant content setting decoration is not
   // visible.
   NSRect GetBlockedPopupRect() const;
 
   virtual void OnAutocompleteAccept(const GURL& url,
       WindowOpenDisposition disposition,
@@ skipping 84 matching lines @@
   // Used to register for notifications received by NotificationObserver.
   NotificationRegistrar registrar_;
 
   // Used to schedule a task for the first run info bubble.
   ScopedRunnableMethodFactory<LocationBarViewMac> first_run_bubble_;
 
   DISALLOW_COPY_AND_ASSIGN(LocationBarViewMac);
 };
 
 #endif  // CHROME_BROWSER_COCOA_LOCATION_BAR_VIEW_MAC_H_