getNonDefaultConfiguration() {
    goog.asserts.assert(this.config_, 'Config must not be null!');

    const ret = this.defaultConfig_();
    shaka.util.PlayerConfiguration.mergeConfigObjects(
        ret, this.config_, this.defaultConfig_());
    return shaka.util.ConfigUtils.getDifferenceFromConfigObjects(
        this.config_, this.defaultConfig_());
  }
Return a copy of the current non default configuration.  Modifications of
the returned value will not affect the Player's active configuration.
You must call <code>player.configure()</code> to make changes.

@return {!Object}
@export