don't clear out all the streams when QBONE shuts done.

It is common that upon session destruction, there are still streams inside the stream map. And QuicSession handles that smoothly.

PiperOrigin-RevId: 344092306
Change-Id: I9391bf227b5b123edd4139d8eff78de4de630a93

quic/qbone/qbone_session_base.cc

diff --git a/quic/qbone/qbone_session_base.cc b/quic/qbone/qbone_session_base.cc
index d2d2ab4..2682a81 100644
--- a/quic/qbone/qbone_session_base.cc
+++ b/quic/qbone/qbone_session_base.cc
@@ -50,12 +50,7 @@
   }
 }
 
-QboneSessionBase::~QboneSessionBase() {
-  // Clear out the streams before leaving this destructor to avoid calling
-  // QuicSession::UnregisterStreamPriority
-  stream_map().clear();
-  closed_streams()->clear();
-}
+QboneSessionBase::~QboneSessionBase() {}
 
 void QboneSessionBase::Initialize() {
   crypto_stream_ = CreateCryptoStream();