public static ApiClientHeaderProvider.Builder defaultApiClientHeaderProviderBuilder() {
    return AdaptationStubSettings.defaultGrpcApiClientHeaderProviderBuilder();
  }
Returns a builder for the default REST ChannelProvider for this service.
java-speech/google-cloud-speech/src/main/java/com/google/cloud/speech/v1p1beta1/stub/AdaptationStubSettings.java