Fix connection close check in quic_client_interop_test_bin

The current connection close check only works if the server sends a
connection close in response to ours. The transport draft doesn't require
that a peer send a connection close in response to a connection close
(though it is the only frame type that can be sent once a connection enters
the closing state). It seems perfectly reasonable to declare the connection
close procedure has completed with a zero error code if we send a
connection close with a zero error code.

gfe-relnote: n/a (test-only tool change)
PiperOrigin-RevId: 293557827
Change-Id: I1fe90fd65703f061e7d920fb7f20380c0ed38162

quic/tools/quic_client_interop_test_bin.cc

diff --git a/quic/tools/quic_client_interop_test_bin.cc b/quic/tools/quic_client_interop_test_bin.cc
index 0ea2c7c..e3abbd1 100644
--- a/quic/tools/quic_client_interop_test_bin.cc
+++ b/quic/tools/quic_client_interop_test_bin.cc
@@ -251,26 +251,10 @@
   }
 
   if (connection->connected()) {
-    test::QuicConnectionPeer::SendConnectionClosePacket(
-        connection, QUIC_NO_ERROR, "Graceful close");
-    const QuicTime close_start_time = epoll_clock.Now();
-    static const auto close_timeout = QuicTime::Delta::FromSeconds(10);
-    while (client->connected()) {
-      client->epoll_network_helper()->RunEventLoop();
-      if (epoll_clock.Now() - close_start_time >= close_timeout) {
-        QUIC_LOG(ERROR) << "Timed out waiting for connection close";
-        AttemptResumption(client.get());
-        return;
-      }
-    }
-    const QuicErrorCode received_error = client->session()->error();
-    if (received_error == QUIC_NO_ERROR ||
-        received_error == QUIC_PUBLIC_RESET) {
-      InsertFeature(Feature::kConnectionClose);
-    } else {
-      QUIC_LOG(ERROR) << "Received error " << client->session()->error() << " "
-                      << client->session()->error_details();
-    }
+    connection->CloseConnection(
+        QUIC_NO_ERROR, "Graceful close",
+        ConnectionCloseBehavior::SEND_CONNECTION_CLOSE_PACKET);
+    InsertFeature(Feature::kConnectionClose);
   }
 
   AttemptResumption(client.get());