anchor.diff:  
   // Increase the build number in the manifest.json file. Returns the full
   // version.
  -String _increaseBuildNumber(GrinderContext context) {
  +String _increaseBuildNumber(GrinderContext context, {bool removeKey: false}) {
     // Tweaking build version in manifest.
     File file = new File('app/manifest.json');
     String content = file.readAsStringSync();
  
positive.code:     return;
    }
  
    String version = _increaseBuildNumber(context);
    // Creating an archive of the Chrome App.
    context.log('Creating build ${version}');
  
    archive(context);
  
    _runCommandSync(
      context,
      'git commit -m "Build version ${version}" app/manifest.json');
  
negative.code: 
    version = '${majorVersion}.${buildVersion}';
    manifestDict['version'] = version;
    if (removeKey) {
      manifestDict.remove('key');
    }
    file.writeAsStringSync(new JsonPrinter().print(manifestDict));
  
    // It needs to be copied to compile result directory.
  