[UI->Navigation] Forward navigation button issue with onbeforeunload dialog

content/browser/web_contents/web_contents_impl.cc

 // 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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <utility>
@@ skipping 4758 matching lines @@
   if (is_showing_before_unload_dialog_ && !success) {
     // It is possible for the current RenderFrameHost to have changed in the
     // meantime.  Do not reset the navigation state in that case.
     if (rfh && rfh == rfh->frame_tree_node()->current_frame_host()) {
       rfh->frame_tree_node()->BeforeUnloadCanceled();
       controller_.DiscardNonCommittedEntries();
     }
 
     FOR_EACH_OBSERVER(WebContentsObserver, observers_,
                       BeforeUnloadDialogCancelled());
+
+    // Notification for UI updates in response to the changed navigation state.
+    NotifyNavigationStateChanged(INVALIDATE_TYPE_LOAD);
   }
 
   is_showing_before_unload_dialog_ = false;
   if (rfh) {
     rfh->JavaScriptDialogClosed(reply_msg, success, user_input,
                                 dialog_was_suppressed);
   } else {
     // Don't leak the sync IPC reply if the RFH or process is gone.
     delete reply_msg;
   }
@@ skipping 176 matching lines @@
   for (RenderViewHost* render_view_host : render_view_host_set)
     render_view_host->OnWebkitPreferencesChanged();
 }
 
 void WebContentsImpl::SetJavaScriptDialogManagerForTesting(
     JavaScriptDialogManager* dialog_manager) {
   dialog_manager_ = dialog_manager;
 }
 
 }  // namespace content