public Builder clearTopic() {
      topic_ = getDefaultInstance().getTopic();
      bitField0_ = (bitField0_ & ~0x00000001);
      onChanged();
      return this;
    }
<pre>
The name of the Pub/Sub topic to publish job completion notification
to. For example: `projects/{project}/topics/{topic}`.
</pre>

<code>string topic = 1;</code>

@return This builder for chaining.
java-video-transcoder/proto-google-cloud-video-transcoder-v1/src/main/java/com/google/cloud/video/transcoder/v1/PubsubDestination.java