anchor.diff:  class ExcelJS {
     /// Executes a batch script that performs actions
     /// on the Excel object model using a new RequestContext.
  -  external static void run(void Function(RequestContext) callback);
  +  external static void run(dynamic Function(RequestContext) callback);
   }
   
   /// Wrapper for Excel.RequestContext class.
  
positive.code:       format.custom.format.fill.color = _underpacingFormatFill;
        format.custom.format.font.color = _underpacingFormatFont;
  
        context.sync();
  
        // All operations are complete.
        formatCompleter.complete();
      }));
  
      return formatCompleter.future;
  
negative.code: 
        format.custom.format.numberFormat = _currencyFormat;
  
        // All operations are complete.
        formatCompleter.complete();
  
        return context.sync();
      }));
  
      return formatCompleter.future;
  