Fix typo in fetch.dart

sky/sdk/lib/framework/net/fetch.dart

Index: sky/sdk/lib/framework/net/fetch.dart
diff --git a/sky/sdk/lib/framework/net/fetch.dart b/sky/sdk/lib/framework/net/fetch.dart
index 5872af30db747d28bde0c8764cf8b7e515c4a2ee..a05f2ab0a9db618a3ab31fc3f0d1124590a1a2cd 100644
--- a/sky/sdk/lib/framework/net/fetch.dart
+++ b/sky/sdk/lib/framework/net/fetch.dart
@@ -44,7 +44,7 @@ Future<UrlResponse> fetchUrl(String relativeUrl) async {
 }
 
 Future<Response> fetchBody(String relativeUrl) async {
-  UrlResponse response = await fetchMojo(relativeUrl);
+  UrlResponse response = await fetchUrl(relativeUrl);
   if (response.body == null) return new Response(null);
 
   ByteData data = await core.DataPipeDrainer.drainHandle(response.body);