static getCodecParts_(codecString) {
    const parts = codecString.split('.');

    const base = parts[0];

    parts.shift();
    const profile = parts.join('.');

    // Make sure that we always return a "base" and "profile".
    return [base, profile];
  }
Get the base and profile of a codec string. Where [0] will be the codec
base and [1] will be the profile.
@param {string} codecString
@return {!Array<string>}
@private