Fixed more HttpRequest documentation.

tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate

 // Copyright (c) 2012, 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.
 
 part of $LIBRARYNAME;
 
 /**
  * A utility for retrieving data from a URL.
  *
  * HttpRequest can be used to obtain data from http, ftp, and file
@@ skipping 36 matching lines @@
    */
   static Future<String> getString(String url,
       {bool withCredentials, void onProgress(ProgressEvent e)}) {
     return request(url, withCredentials: withCredentials,
         onProgress: onProgress).then((xhr) => xhr.responseText);
   }
 
   /**
    * Makes a server POST request with the specified data encoded as form data.
    *
-   * This is similar to sending a FormData object with broader browser
-   * support but limited to string values.
+   * This is roughly the POST equivalent of getString. This method is similar 
+   * to sending a FormData object with broader browser support but limited to 
+   * String values.
    *
    * See also:
    *
    * * [request]
    */
   static Future<HttpRequest> postFormData(String url, Map<String, String> data,
       {bool withCredentials, String responseType,
       Map<String, String> requestHeaders,
       void onProgress(ProgressEvent e)}) {
 
@@ skipping 12 matching lines @@
 
     return request(url, method: 'POST', withCredentials: withCredentials,
         responseType: responseType,
         requestHeaders: requestHeaders, sendData: formData,
         onProgress: onProgress);
   }
 
   /**
    * Creates a URL request for the specified [url].
    *
-   * By default this will do an HTTP GET request, this can be overridden with
-   * [method].
+   * By default `request` will perform an HTTP GET request, but a different
+   * method (`POST`, `PUT`, `DELETE`, etc) can be used by specifying the 
+   * [method] parameter.
    *
    * The Future is completed when the response is available.
    *
+   * If specified, `sendData` will send data in the form of a [ByteBuffer],
+   * [Blob], [Document], [String], or [FormData] along with the HttpRequest.
+   *
    * The [withCredentials] parameter specified that credentials such as a cookie
    * (already) set in the header or
    * [authorization headers](http://tools.ietf.org/html/rfc1945#section-10.2)
    * should be specified for the request. Details to keep in mind when using
    * credentials:
    *
    * * Using credentials is only useful for cross-origin requests.
    * * The `Access-Control-Allow-Origin` header of `url` cannot contain a wildcard (*).
    * * The `Access-Control-Allow-Credentials` header of `url` must be set to true.
    * * If `Access-Control-Expose-Headers` has not been set to true, only a subset of all the response headers will be returned when calling [getAllRequestHeaders].
@@ skipping 156 matching lines @@
     } else {
       JS('', '#.send()', xhr);
     }
 
     return completer.future;
 $endif
   }
 
 $!MEMBERS
 }