anchor.diff:    group("object upload", () {
       test("should be able to successfully initialise an upload", () {
         Future<http.StreamedResponse> streamHandler(http.BaseRequest request, http.ByteStream bodyStream) {
  -        expect(request.headers['X-UploadContent-Type'], 'text/plain');
  +        expect(request.headers['X-Upload-Content-Type'], 'text/plain');
           expect(request.headers['X-Upload-Content-Length'], '26');
           expect(request.headers['X-Upload-Content-MD5'], 'w/zT12GS5AB9+0lsymfhOw==');
           expect(request.headers['content-type'], 'application/json; charset=UTF-8');
  
positive.code: 
        var connection = new Connection(
            'proj_id',
            (http.BaseRequest request) {
              return new MockClient.streaming(streamHandler).send(request);
            }
        );
  
        var src = new StringSource("abcdefghijklmnopqrstuvwxyz");
  
negative.code: 
      var connection = new Connection(
          'proj_id',
          new MockClient.streaming(streamHandler)
      );
  
      connection.logger.onRecord.listen(print);
  