code: function createMergedResultFunction(one, two) {
      return function mergedResult() {
        var a = one.apply(this, arguments);
        var b = two.apply(this, arguments);
        if (a == null) {
          return b;
        } else if (b == null) {
          return a;
        }
        var c = {};
        mergeIntoWithNoDuplicateKeys(c, a);
        mergeIntoWithNoDuplicateKeys(c, b);
        return c;
      };
    }
docs: Creates a function that invokes two functions and merges their return values.
  
  @param {function} one Function to invoke first.
  @param {function} two Function to invoke second.
  @return {function} Function that invokes the two argument functions.
  @private