Add 'XHR' to the Resource::Type enum, and use it for XHR requests.

Source/core/fetch/CrossOriginAccessControl.cpp

 /*
  * Copyright (C) 2008 Apple 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.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 98 matching lines @@
         request.setHTTPOrigin(securityOrigin->toAtomicString());
 }
 
 ResourceRequest createAccessControlPreflightRequest(const ResourceRequest& request, SecurityOrigin* securityOrigin)
 {
     ResourceRequest preflightRequest(request.url());
     updateRequestForAccessControl(preflightRequest, securityOrigin, DoNotAllowStoredCredentials);
     preflightRequest.setHTTPMethod("OPTIONS");
     preflightRequest.setHTTPHeaderField("Access-Control-Request-Method", request.httpMethod());
     preflightRequest.setPriority(request.priority());
+    preflightRequest.setTargetType(request.targetType());
 
     const HTTPHeaderMap& requestHeaderFields = request.httpHeaderFields();
 
     if (requestHeaderFields.size() > 0) {
         StringBuilder headerBuffer;
         HTTPHeaderMap::const_iterator it = requestHeaderFields.begin();
         headerBuffer.append(it->key);
         ++it;
 
         HTTPHeaderMap::const_iterator end = requestHeaderFields.end();
@@ skipping 137 matching lines @@
         request.setHTTPOrigin(securityOrigin->toAtomicString());
         // If the user didn't request credentials in the first place, update our
         // state so we neither request them nor expect they must be allowed.
         if (options.credentialsRequested == ClientDidNotRequestCredentials)
             options.allowCredentials = DoNotAllowStoredCredentials;
     }
     return true;
 }
 
 } // namespace WebCore