read_rows stream resumption not working?

[igorbernstein2]

Running the following snippet:

client = bigtable.Client(project="google.com:cloud-bigtable-dev")
instance = client.instance("igorbernstein-dev")
table = instance.table("table1")

rows = table.read_rows(start_key="a", end_key="b", retry=bigtable.table.DEFAULT_RETRY_READ_ROWS.with_deadline(2.0))
for r in rows:
 print(f'row:{r}\n')

Against a java emulator:

public static void main(String[] args) throws Exception {
 Server server =
 ServerBuilder.forPort(1234)
 .addService(
 new BigtableImplBase() {
 @Override
 public void readRows(
 ReadRowsRequest request, StreamObserver<ReadRowsResponse> responseObserver) {
 System.out.println(Context.current().getDeadline());
 try {
 Thread.sleep(100);
 } catch (InterruptedException e) {
 responseObserver.onError(e);
 return;
 }
 responseObserver.onError(Status.UNAVAILABLE.asException());
 }
 })
 .build();

 server.start();
 server.awaitTermination();
 }

I would expect to see multiple attempt rpcs spaced with exponential delay. But I only see one

[Mariatta]

I found that the retry wasn't being passed to the grpc read_rows call.
When I added the retry parameter (shown in the PR), using the emulator code you provided, then I could see that a retry attempt was made.

Prior to this code change, using the emulator I saw only one request incoming. After this change, I could see the second request in the emulator.

Would this be a reasonable fix? #759