code: function(newParams) {
          if (this.requestEncoding.toUpperCase() === "KVP") {
              return OpenLayers.Layer.Grid.prototype.mergeNewParams.apply(
                  this, [OpenLayers.Util.upperCaseObject(newParams)]
              );
          }
      }
docs: APIMethod: mergeNewParams
  Extend the existing layer <params> with new properties.  Tiles will be
  reloaded with updated params in the request.
  
  Parameters:
  newParams - {Object} Properties to extend to existing <params>.