Updated documentation for HttpRequest.

sdk/lib/html/dart2js/html_dart2js.dart

Index: sdk/lib/html/dart2js/html_dart2js.dart
diff --git a/sdk/lib/html/dart2js/html_dart2js.dart b/sdk/lib/html/dart2js/html_dart2js.dart
index 84ebc80eeacff04e78e7e5dd16dea8a8a9dc4090..6519e0284ef695f0f409012e3769088fd393f635 100644
--- a/sdk/lib/html/dart2js/html_dart2js.dart
+++ b/sdk/lib/html/dart2js/html_dart2js.dart
@@ -2045,6 +2045,7 @@ class CanvasRenderingContext2D extends CanvasRenderingContext native "CanvasRend
   /** Deprecated always returns 1.0 */
   @DomName('CanvasRenderingContext2D.webkitBackingStorePixelRation')
   @Experimental()
+  @deprecated
   double get backingStorePixelRatio => 1.0;
 }
 
@@ -14671,13 +14672,19 @@ class HttpRequest extends HttpRequestEventTarget native "XMLHttpRequest" {
    *
    * 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)