Updated documentation for HttpRequest.

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

Index: tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
diff --git a/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate b/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
index 539e645ac913da012101119d036c7d38e6a7c542..e8f64d558e2463268fe0a1dd6c6f27434b67efb2 100644
--- a/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
+++ b/tools/dom/templates/html/impl/impl_XMLHttpRequest.darttemplate
@@ -137,13 +137,19 @@ $(ANNOTATIONS)$(CLASS_MODIFIERS)class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
    *
    * 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.
+   * [method] parameter. (See also [HttpRequest.postFormData] for `POST` 
+   * requests only.
    *
    * 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.
    *
+   * If specified, [responseType] sets the desired response format for the
+   * request. By default it is [String], but can also be 'arraybuffer', 'blob', 
+   * 'document', 'json', or 'text'. See also [HttpRequest.responseType] 
+   * for more information.
+   *
    * 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)