function filterSuite(callback) {
      var suite = this,
          result = new suite.constructor(suite.options);

      result.push.apply(result, filter(suite, callback));
      return result;
    }
An `Array#filter` like method.

@name filter
@memberOf Benchmark.Suite
@param {Function|string} callback The function/alias called per iteration.
@returns {Object} A new suite of benchmarks that passed callback filter.