code: function _isReservedShortcuts(normalizedKey) {
          if (!normalizedKey) {
              return false;
          }
  
          if (_reservedShortcuts.indexOf(normalizedKey) > -1 ||
                  _reservedShortcuts.indexOf(normalizedKey.replace("Cmd", "Ctrl")) > -1) {
              return true;
          }
  
          if (brackets.platform === "mac" && _macReservedShortcuts.indexOf(normalizedKey) > -1) {
              return true;
          }
  
          return false;
      }
docs: @private
  
  Checks whether the given key combination is a shortcut of a special command
  or a Mac system command that the user can't reassign to another command.
  @param {!string} normalizedKey A key combination string used for a keyboard shortcut
  @return {boolean} true if normalizedKey is a restricted shortcut, false otherwise.