[Mac] Address buggy permission bubble behaviour on dismissal via ESC.

chrome/browser/permissions/permission_request_manager.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_PERMISSIONS_PERMISSION_REQUEST_MANAGER_H_
 #define CHROME_BROWSER_PERMISSIONS_PERMISSION_REQUEST_MANAGER_H_
 
 #include <unordered_map>
 #include <vector>
 
@@ skipping 52 matching lines @@
 
   // Cancels an outstanding request. This may have different effects depending
   // on what is going on with the bubble. If the request is pending, it will be
   // removed and never shown. If the request is showing, it will continue to be
   // shown, but the user's action won't be reported back to the request object.
   // In some circumstances, we can remove the request from the bubble, and may
   // do so. The request will have RequestFinished executed on it if it is found,
   // at which time the caller is free to delete the request.
   void CancelRequest(PermissionRequest* request);
 
-  // Hides the bubble.
+  // Temporarily hides the bubble, and destroys the prompt UI surface. Any
+  // existing requests will be reshown when DisplayPendingRequests is called
+  // (e.g. when switching tabs away and back to a page with a prompt).
   void HideBubble();
 
   // Will show a permission bubble if there is a pending permission request on
   // the web contents that the PermissionRequestManager belongs to.
   void DisplayPendingRequests();
 
   // Will reposition the bubble (may change parent if necessary).
   void UpdateAnchorPosition();
 
   // True if a permission bubble is currently visible.
@@ skipping 113 matching lines @@
   // Whether each of the requests in |requests_| is accepted by the user.
   std::vector<bool> accept_states_;
 
   base::ObserverList<Observer> observer_list_;
   AutoResponseType auto_response_for_test_;
 
   base::WeakPtrFactory<PermissionRequestManager> weak_factory_;
 };
 
 #endif  // CHROME_BROWSER_PERMISSIONS_PERMISSION_REQUEST_MANAGER_H_