Get rid of unneeded Future.immediate() calls.

utils/pub/http.dart

 // 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.
 
 /// Helpers for dealing with HTTP.
 library pub.http;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:json' as json;
@@ skipping 32 matching lines @@
 
     // TODO(nweiz): Ideally the timeout would extend to reading from the
     // response input stream, but until issue 3657 is fixed that's not feasible.
     return timeout(inner.send(request).then((streamedResponse) {
       log.fine("Got response ${streamedResponse.statusCode} "
                "${streamedResponse.reasonPhrase}.");
 
       var status = streamedResponse.statusCode;
       // 401 responses should be handled by the OAuth2 client. It's very
       // unlikely that they'll be returned by non-OAuth2 requests.
-      if (status < 400 || status == 401) {
-        return new Future.immediate(streamedResponse);
-      }
+      if (status < 400 || status == 401) return streamedResponse;
 
       return http.Response.fromStream(streamedResponse).then((response) {
         throw new PubHttpException(response);
       });
     }).catchError((asyncError) {
       if (asyncError.error is SocketIOException &&
           asyncError.error.osError != null &&
           (asyncError.error.osError.errorCode == 8 ||
            asyncError.error.osError.errorCode == -2 ||
            asyncError.error.osError.errorCode == -5 ||
@@ skipping 61 matching lines @@
 
 /// Exception thrown when an HTTP operation fails.
 class PubHttpException implements Exception {
   final http.Response response;
 
   const PubHttpException(this.response);
 
   String toString() => 'HTTP error ${response.statusCode}: '
       '${response.reasonPhrase}';
 }