--- /dev/null
+// Copyright 2013 The Closure Library Authors. All Rights Reserved.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS-IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+goog.provide('goog.net.XhrLike');
+
+
+
+/**
+ * Interface for the common parts of XMLHttpRequest.
+ *
+ * Mostly copied from externs/w3c_xml.js.
+ *
+ * @interface
+ * @see http://www.w3.org/TR/XMLHttpRequest/
+ */
+goog.net.XhrLike = function() {};
+
+
+/**
+ * Typedef that refers to either native or custom-implemented XHR objects.
+ * @typedef {!goog.net.XhrLike|!XMLHttpRequest}
+ */
+goog.net.XhrLike.OrNative;
+
+
+/**
+ * @type {function()|null|undefined}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#handler-xhr-onreadystatechange
+ */
+goog.net.XhrLike.prototype.onreadystatechange;
+
+
+/**
+ * @type {string}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-responsetext-attribute
+ */
+goog.net.XhrLike.prototype.responseText;
+
+
+/**
+ * @type {Document}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-responsexml-attribute
+ */
+goog.net.XhrLike.prototype.responseXML;
+
+
+/**
+ * @type {number}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#readystate
+ */
+goog.net.XhrLike.prototype.readyState;
+
+
+/**
+ * @type {number}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#status
+ */
+goog.net.XhrLike.prototype.status;
+
+
+/**
+ * @type {string}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#statustext
+ */
+goog.net.XhrLike.prototype.statusText;
+
+
+/**
+ * @param {string} method
+ * @param {string} url
+ * @param {?boolean=} opt_async
+ * @param {?string=} opt_user
+ * @param {?string=} opt_password
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-open()-method
+ */
+goog.net.XhrLike.prototype.open = function(method, url, opt_async, opt_user,
+ opt_password) {};
+
+
+/**
+ * @param {ArrayBuffer|ArrayBufferView|Blob|Document|FormData|string=} opt_data
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-send()-method
+ */
+goog.net.XhrLike.prototype.send = function(opt_data) {};
+
+
+/**
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-abort()-method
+ */
+goog.net.XhrLike.prototype.abort = function() {};
+
+
+/**
+ * @param {string} header
+ * @param {string} value
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-setrequestheader()-method
+ */
+goog.net.XhrLike.prototype.setRequestHeader = function(header, value) {};
+
+
+/**
+ * @param {string} header
+ * @return {string}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-getresponseheader()-method
+ */
+goog.net.XhrLike.prototype.getResponseHeader = function(header) {};
+
+
+/**
+ * @return {string}
+ * @see http://www.w3.org/TR/XMLHttpRequest/#the-getallresponseheaders()-method
+ */
+goog.net.XhrLike.prototype.getAllResponseHeaders = function() {};