code: function setGlobalLogger(fn) {
    for (let klass of [ContextMenuBuilder, ContextMenuListener, SpellCheckHandler]) {
      klass.setLogger(fn);
    }
  }
docs: Overrides the default logging function (the `debug` library) with another
  logger.
  
  @param {Function}  fn    The `console.log` like function that will write debug
  information to.