getBandwidthEstimate(defaultEstimate) {
    const estimatedThroughput = this.getEstimatedThroughput();
    if (!estimatedThroughput) {
      return defaultEstimate;
    }
    const etpWeightRatio = this.config_.estimatedThroughputWeightRatio;
    if (etpWeightRatio > 0 && etpWeightRatio <= 1) {
      return (defaultEstimate * (1 - etpWeightRatio)) +
          (estimatedThroughput * etpWeightRatio);
    }
    return defaultEstimate;
  }
Gets the current bandwidth estimate.

@param {number} defaultEstimate
@return {number} The bandwidth estimate in bits per second.
@export