Create ResourceProgressEvent, expose as Chromium API

Source/WebKit/chromium/src/WebDOMEvent.cpp

 /*
  * Copyright (C) 2010 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 38 matching lines @@
 }
 
 void WebDOMEvent::assign(const WebDOMEvent& other)
 {
     WebDOMEventPrivate* p = const_cast<WebDOMEventPrivate*>(other.m_private);
     if (p)
         p->ref();
     assign(p);
 }
 
-void WebDOMEvent::assign(WebDOMEventPrivate* p)
+void WebDOMEvent::assign(WebDOMEventPrivate* event)
 {
-    // p is already ref'd for us by the caller
+    // event is already ref'd for us by the caller
     if (m_private)
         m_private->deref();

[abarth-chromium, 2013/05/20 21:16:32]

Ouch.  We should remove this function.  It's asking for a use-after-free.

[dmichael (off chromium), 2013/05/23 16:47:00]

Good point, I fixed it in a separate CL:
https://codereview.chromium.org/15271012/

-    m_private = p;
+    m_private = event;
+}
+
+void WebDOMEvent::assign(const WTF::PassRefPtr<WebDOMEventPrivate>& event)
+{
+    assign(event.leakRef());

[abarth-chromium, 2013/05/20 21:16:32]

Can't we just assign m_private directly?  The raw version of this function is
bad news bears.

[dmichael (off chromium), 2013/05/23 16:47:00]

Done.

 }
 
 WebDOMEvent::WebDOMEvent(const WTF::PassRefPtr<WebCore::Event>& event)
     : m_private(static_cast<WebDOMEventPrivate*>(event.leakRef()))
 {
 }
 
 WebDOMEvent::operator WTF::PassRefPtr<WebCore::Event>() const
 {
     return static_cast<WebCore::Event*>(m_private);
@@ skipping 131 matching lines @@
     return m_private->hasInterface(eventNames().interfaceForXMLHttpRequestProgressEvent);
 }
 
 bool WebDOMEvent::isBeforeLoadEvent() const
 {
     ASSERT(m_private);
     return m_private->hasInterface(eventNames().interfaceForBeforeLoadEvent);
 }
 
 } // namespace WebKit