public static ApiClientHeaderProvider.Builder defaultGrpcApiClientHeaderProviderBuilder() {
    return ApiClientHeaderProvider.newBuilder()
        .setGeneratedLibToken("gapic", GaxProperties.getLibraryVersion(SpeechStubSettings.class))
        .setTransportToken(
            GaxGrpcProperties.getGrpcTokenName(), GaxGrpcProperties.getGrpcVersion());
  }
Returns a builder for the default REST ChannelProvider for this service.
java-speech/google-cloud-speech/src/main/java/com/google/cloud/speech/v2/stub/SpeechStubSettings.java