public Builder clearDefaultSlate() {
      defaultSlate_ = getDefaultInstance().getDefaultSlate();
      bitField0_ = (bitField0_ & ~0x00000040);
      onChanged();
      return this;
    }
<pre>
This must refer to a slate in the same
project. If Google Ad Manager (GAM) is used for ads, this string sets the
value of `slateCreativeId` in
https://developers.google.com/ad-manager/api/reference/v202211/LiveStreamEventService.LiveStreamEvent#slateCreativeId
</pre>

<code>string default_slate = 7 [(.google.api.resource_reference) = { ... }</code>

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