Set navigationStart correctly for all load types.

third_party/WebKit/public/web/WebFrameClient.h

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 326 matching lines @@
     // This method may not execute JavaScript code.
     virtual void didFinishDocumentLoad(WebLocalFrame*) { }
 
     // Like |didFinishDocumentLoad|, except this method may run JavaScript
     // code (and possibly invalidate the frame).
     virtual void runScriptsAtDocumentReady(WebLocalFrame*, bool documentIsEmpty) { }
 
     // The 'load' event was dispatched.
     virtual void didHandleOnloadEvents(WebLocalFrame*) { }
 
+    // The 'beforeunload' event was dispatched, a dialog probably was shown, and
+    // the navigation is not aborted.  |eventListenerCalled| is true if at least
+    // one frame (in the tree that is being closed) had a beforeunload event
+    // handler invoked.
+    virtual void didHandleOnBeforeUnloadEvent(bool eventListenerCalled) {}
+
     // The frame's document or one of its subresources failed to load. The
     // WebHistoryCommitType is the commit type that would have been used had the
     // load succeeded.
     virtual void didFailLoad(WebLocalFrame*, const WebURLError&, WebHistoryCommitType) { }
 
     // The frame's document and all of its subresources succeeded to load.
     virtual void didFinishLoad(WebLocalFrame*) { }
 
     // The navigation resulted in no change to the documents within the page.
     // For example, the navigation may have just resulted in scrolling to a
@@ skipping 361 matching lines @@
     // Mojo ----------------------------------------------------------------
     virtual ServiceRegistry* serviceRegistry() { return nullptr; }
 
 protected:
     virtual ~WebFrameClient() { }
 };
 
 } // namespace blink
 
 #endif