anchor.diff:            String bName = b.isBlob ? b.name : (b.name + '/');
             return aName.compareTo(bName);
           });
  -        store.writeTree(treeEntries).then((String result) {
  -          completer.complete(result);
  -        });
  +        return store.writeTree(treeEntries);
         });
       });
  -
  -    return completer.future;
     }
   
     static Future checkTreeChanged(ObjectStore store, String parent,
  
positive.code:               treeEntries.add(new TreeEntry(entry.name, shaToBytes(sha),
                    false));
              }
              return;
            });
          } else {
            (entry as chrome.ChromeFileEntry).readBytes().then(
  
negative.code:             store.writeRawObject('blob', new Uint8List.fromList(
                  buf.getBytes())).then((String sha) {
                treeEntries.add(new TreeEntry(entry.name, shaToBytes(sha), true));
              });
            });
          }
  