[DevTools] Add dialog type and return value to Page.javascriptDialog{Opening,Closed}.

Source/web/ChromeClientImpl.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  *
  * 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.
@@ skipping 390 matching lines @@
 
     // Make sure that all loading is stopped.  Ensures that JS stops executing!
     m_webView->mainFrame()->stopLoading();
 
     if (m_webView->client())
         m_webView->client()->closeWidgetSoon();
 }
 
 // Although a LocalFrame is passed in, we don't actually use it, since we
 // already know our own m_webView.
-void ChromeClientImpl::openJavaScriptAlertDelegate(LocalFrame* frame, const String& message)
+bool ChromeClientImpl::openJavaScriptAlertDelegate(LocalFrame* frame, const String& message)
 {
     notifyPopupOpeningObservers();
     WebLocalFrameImpl* webframe = WebLocalFrameImpl::fromFrame(frame);
     if (webframe->client()) {
         if (WebUserGestureIndicator::isProcessingUserGesture())
             WebUserGestureIndicator::currentUserGestureToken().setJavascriptPrompt();
         webframe->client()->runModalAlertDialog(message);
+        return true;
     }
+    return false;
 }
 
 // See comments for openJavaScriptAlertDelegate().
 bool ChromeClientImpl::openJavaScriptConfirmDelegate(LocalFrame* frame, const String& message)
 {
     notifyPopupOpeningObservers();
     WebLocalFrameImpl* webframe = WebLocalFrameImpl::fromFrame(frame);
     if (webframe->client()) {
         if (WebUserGestureIndicator::isProcessingUserGesture())
             WebUserGestureIndicator::currentUserGestureToken().setJavascriptPrompt();
@@ skipping 520 matching lines @@
 }
 
 void ChromeClientImpl::notifyPopupOpeningObservers() const
 {
     const Vector<PopupOpeningObserver*> observers(m_popupOpeningObservers);
     for (const auto& observer : observers)
         observer->willOpenPopup();
 }
 
 } // namespace blink