Rename XMLHttpRequest to HttpRequest.

samples/webcomponents/shadow_polyfill.dart

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /**
  * Polyfill script for custom elements. To use this script, your app must
  * create a CustomElementsManager with the appropriate lookup function before
  * doing any DOM queries or modifications.
  * Currently, all custom elements must be registered with the polyfill.  To
  * register custom elements, provide the appropriate lookup function to your
  * CustomElementsManager.
  *
  * This script only works at present in dart2js, but it should work in dartium
- * soon (pending MutationObservers). The script does an XMLHTTP request, so
+ * soon (pending MutationObservers). The script does an HTTP request, so
  * to test using locally defined custom elements you must run chrome with the
  * flag -allow-file-access-from-files.
  */
 
 #library('webcomponents');
 
 #import('dart:html');
 
 #source('list_map.dart');
 
@@ skipping 63 matching lines @@
   void _loadComponents() {
     queryAll('link[rel=components]').forEach((link) => _load(link.href));
     _expandDeclarations();
   }
 
   /**
    * Load the document at the given url and parse it to extract
    * custom element declarations.
    */
   void _load(String url) {
-    var request = new XMLHttpRequest();
+    var request = new HttpRequest();
     // We use a blocking request here because no Dart is allowed to run
     // until DOM content is loaded.
     // TODO(samhop): give a decent timeout message if custom elements fail to
     // load
     request.open('GET', url, async: false);
     request.on.readyStateChange.add((Event e) {
       if (request.readyState == REQUEST_DONE) {
         if (request.status >= 200 && request.status < 300
             || request.status == 304 || request.status == 0) {
           var declarations = _parse(request.response);
@@ skipping 229 matching lines @@
       }
     });
     attributeObserver.observe(e, attributes: true, attributeOldValue: true);
 
     // Listen for all insertions and deletions on the DOM so that we can
     // catch custom elements being inserted and call the appropriate callbacks.
     manager.initializeInsertedRemovedCallbacks(shadowRoot);
     return newCustomElement;
   }
 }