manualLowercase = function(s) {
  return isString(s)
      ? s.replace(/[A-Z]/g, function(ch) {return fromCharCode(ch.charCodeAt(0) | 32);})
      : s;
}
@ngdoc function
@name angular.uppercase
@function

@description Converts the specified string to uppercase.
@param {string} string String to be converted to uppercase.
@returns {string} Uppercased string.