Expose outgoingReferrer() to WebDocument.

Source/web/WebDocument.cpp

 /*
  * Copyright (C) 2009 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 244 matching lines @@
     if (exceptionState.hadException())
         return WebDOMEvent();
     return event;
 }
 
 WebReferrerPolicy WebDocument::referrerPolicy() const
 {
     return static_cast<WebReferrerPolicy>(constUnwrap<Document>()->referrerPolicy());
 }
 
+WebString WebDocument::outgoingReferrer()
+{
+    return WebString(unwrap<Document>()->outgoingReferrer());

[Mike West, 2015/08/20 20:07:25]

Nit: Can this be `constUnwrap`?

+}
+
 WebElement WebDocument::createElement(const WebString& tagName)
 {
     TrackExceptionState exceptionState;
     WebElement element(unwrap<Document>()->createElement(tagName, exceptionState));
     if (exceptionState.hadException())
         return WebElement();
     return element;
 }
 
 WebAXObject WebDocument::accessibilityObject() const
@@ skipping 70 matching lines @@
     m_private = elem;
     return *this;
 }
 
 WebDocument::operator PassRefPtrWillBeRawPtr<Document>() const
 {
     return toDocument(m_private.get());
 }
 
 } // namespace blink