Update to set flags=0 on all ops

src/cpp/server/server_context.cc

diff --git a/src/cpp/server/server_context.cc b/src/cpp/server/server_context.cc
index eea9645..699895a 100644
--- a/src/cpp/server/server_context.cc
+++ b/src/cpp/server/server_context.cc
@@ -79,6 +79,7 @@
 void ServerContext::CompletionOp::FillOps(grpc_op* ops, size_t* nops) {
   ops->op = GRPC_OP_RECV_CLOSE_ON_SERVER;
   ops->data.recv_close_on_server.cancelled = &cancelled_;
+  ops->flags = 0;
   *nops = 1;
 }