Update tests on HTTP/3 unidirectional streams.

Those streams should be created in a style similar to how they are created in real QuicSpdySession.

gfe-relnote: test only change, no behavior change.
PiperOrigin-RevId: 262616474
Change-Id: Ibbd5ff50043091c6e6ce5ef8380199b57988270b
diff --git a/quic/core/qpack/qpack_send_stream_test.cc b/quic/core/qpack/qpack_send_stream_test.cc
index 46037c9..9eb6471 100644
--- a/quic/core/qpack/qpack_send_stream_test.cc
+++ b/quic/core/qpack/qpack_send_stream_test.cc
@@ -56,9 +56,15 @@
             SupportedVersions(GetParam().version))),
         session_(connection_) {
     session_.Initialize();
-    qpack_send_stream_ = QuicMakeUnique<QpackSendStream>(
+
+    // TODO(b/112770235): Remove explicit QPACK stream construction in test once
+    // QPACK streams are created in QuicSpdySession initialization.
+    auto qpack_send = QuicMakeUnique<QpackSendStream>(
         QuicSpdySessionPeer::GetNextOutgoingUnidirectionalStreamId(&session_),
         &session_, kQpackEncoderStream);
+    qpack_send_stream_ = qpack_send.get();
+    session_.RegisterStaticStream(std::move(qpack_send), false);
+
     ON_CALL(session_, WritevData(_, _, _, _, _))
         .WillByDefault(Invoke(MockQuicSession::ConsumeData));
   }
@@ -69,7 +75,7 @@
   MockAlarmFactory alarm_factory_;
   StrictMock<MockQuicConnection>* connection_;
   StrictMock<MockQuicSpdySession> session_;
-  std::unique_ptr<QpackSendStream> qpack_send_stream_;
+  QpackSendStream* qpack_send_stream_;
 };
 
 INSTANTIATE_TEST_SUITE_P(Tests,