fix

Author: sushanb

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/data/v2/stub/BigtableChannelPrimer.java

@@ -29,10 +29,10 @@
 import io.grpc.Channel;
 import io.grpc.ClientCall;
 import io.grpc.Deadline;
-import io.grpc.ManagedChannel;
 import io.grpc.Metadata;
 import io.grpc.Status;
 import io.grpc.auth.MoreCallCredentials;
+
 import java.io.IOException;
 import java.io.UnsupportedEncodingException;
 import java.net.URLEncoder;

google-cloud-bigtable/src/main/java/com/google/cloud/bigtable/gaxx/grpc/BigtableTransportChannelProvider.java

@@ -206,6 +206,12 @@ public TransportChannel getTransportChannel() throws IOException {
       selectedProvider = (InstantiatingGrpcChannelProvider) delegate.withHeaders(fallbackHeaders);
     }
 
+
+    if (maybeDirectAccessChannel instanceof ManagedChannel) {
+      // call shutdown
+      ((ManagedChannel) maybeDirectAccessChannel).shutdownNow();
+    }
+
     // This provider's main purpose is to replace the default GAX ChannelPool
     // with a custom BigtableChannelPool, reusing the delegate's configuration.
 
@@ -259,7 +265,7 @@ public TransportChannelProvider withCredentials(Credentials credentials) {
     InstantiatingGrpcChannelProvider newChannelProvider =
         (InstantiatingGrpcChannelProvider) delegate.withCredentials(credentials);
     return new BigtableTransportChannelProvider(
-        newChannelProvider, channelPrimer, channelPoolMetricsTracer, backgroundExecutor, );
+        newChannelProvider, channelPrimer, channelPoolMetricsTracer, backgroundExecutor, headers);
   }
 
   /** Creates a BigtableTransportChannelProvider. */