Converting XHR from onLoad to onReadyStateChange

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 76 matching lines @@
     }
 
     if (responseType != null) {
       xhr.responseType = responseType;
     }
 
     if (onProgress != null) {
       xhr.onProgress.listen(onProgress);
     }
 
-    xhr.onLoad.listen((e) {
-      if (xhr.status >= 200 && xhr.status < 300 ||
-          xhr.status == 304 ) {
-        completer.complete(xhr);
-      } else {
-        completer.completeError(e);
+    xhr.onReadyStateChange.listen((e) {
+      if (xhr.readyState == HttpRequest.DONE) {
+        if (xhr.status >= 200 && xhr.status < 300 ||
+            xhr.status == 304 ) {

[Emily Fortuna, 2013/02/07 20:53:44]

This doesn't fix the problem described in dartbug.com/8401. What you should do
instead is run this branch if the status is also 0 (you can check if the request
is for a file URL specifically). The problem is status will be 0 for a local
file, regardless of whether or not it is actually "found"! So, completing as
opposed to completeError in that one case could be slightly misleading. That's
why I didn't have an actual error condition in the previous version of this
code. I think the flow described though is probably the least strange for most
cases.

+          completer.complete(xhr);
+        } else {
+          completer.completeError(e);
+        }
       }
     });
 
     xhr.onError.listen((e) {
       completer.completeError(e);
     });
 
     if (sendData != null) {
       xhr.send(sendData);
     } else {
       xhr.send();
     }
 
     return completer.future;
   }
 
 $!MEMBERS
 }