public Builder clearTotalBilledDuration() {
      bitField0_ = (bitField0_ & ~0x00000002);
      totalBilledDuration_ = null;
      if (totalBilledDurationBuilder_ != null) {
        totalBilledDurationBuilder_.dispose();
        totalBilledDurationBuilder_ = null;
      }
      onChanged();
      return this;
    }
<pre>
When available, billed audio seconds for the corresponding request.
</pre>

<code>.google.protobuf.Duration total_billed_duration = 2;</code>
java-speech/proto-google-cloud-speech-v2/src/main/java/com/google/cloud/speech/v2/BatchRecognizeResponse.java