Don't commit the blocked URL when a frame is blocked by XFrameOptions.

third_party/WebKit/Source/core/loader/DocumentLoader.cpp

 /*
  * Copyright (C) 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2011 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:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
@@ skipping 344 matching lines @@
         return false;
     return true;
 }
 
 void DocumentLoader::cancelLoadAfterXFrameOptionsOrCSPDenied(const ResourceResponse& response)
 {
     InspectorInstrumentation::continueAfterXFrameOptionsDenied(m_frame, this, mainResourceIdentifier(), response, m_mainResource.get());
 
     setWasBlockedAfterXFrameOptionsOrCSP();
 
-    // Pretend that this was an empty HTTP 200 response.
+    // Pretend that this was an empty HTTP 200 response.  Don't reuse the
+    // original URL for the empty page (https://crbug.com/622385).
+    //
+    // TODO(mkwst):  Remove this once XFO moves to the browser.
+    // https://crbug.com/555418.
     clearMainResourceHandle();
-    m_response = ResourceResponse(blankURL(), "text/html", 0, nullAtom, String());
+    KURL blockedURL = SecurityOrigin::urlWithUniqueSecurityOrigin();
+    m_originalRequest.setURL(blockedURL);
+    m_request.setURL(blockedURL);
+    m_redirectChain.removeLast();
+    appendRedirect(blockedURL);
+    m_response = ResourceResponse(blockedURL, "text/html", 0, nullAtom, String());
     finishedLoading(monotonicallyIncreasingTime());
 
     return;
 }
 
 void DocumentLoader::responseReceived(Resource* resource, const ResourceResponse& response, PassOwnPtr<WebDataConsumerHandle> handle)
 {
     ASSERT_UNUSED(resource, m_mainResource == resource);
     ASSERT_UNUSED(handle, !handle);
     ASSERT(frame());
@@ skipping 324 matching lines @@
 {
     m_writer = createWriterFor(init, mimeType(), m_writer ? m_writer->encoding() : emptyAtom, true, ForceSynchronousParsing);
     if (!source.isNull())
         m_writer->appendReplacingData(source);
     endWriting(m_writer.get());
 }
 
 DEFINE_WEAK_IDENTIFIER_MAP(DocumentLoader);
 
 } // namespace blink