code: public static void setupTracingConfig() {
      List<String> descriptors = new ArrayList<>();
      addDescriptor(descriptors, BigtableTableAdminGrpc.getServiceDescriptor());
      addDescriptor(descriptors, BigtableGrpc.getServiceDescriptor());
  
      Tracing.getExportComponent().getSampledSpanStore().registerSpanNamesForCollection(descriptors);
    }
docs: This is a one time setup for grpcz pages. This adds all of the methods to the Tracing
  environment required to show a consistent set of methods relating to Cloud Bigtable on the
  grpcz page.  If HBase artifacts are present, this will add tracing metadata for HBase methods.