Add QuicDispatcherPeer::GetTimeWaitListManager() method.

This is so that redefining QuicDispatcherPeer could be avoided at
https://github.com/envoyproxy/envoy/blob/master/test/extensions/quic_listeners/quiche/envoy_quic_dispatcher_test.cc#L41.
Such a redefinition makes it impossible to use other
QuicDispatcherPeer methods or to include
test_tools/quic_dispatcher_peer.h at all from Envoy.

gfe-relnote: n/a, test-only change.
PiperOrigin-RevId: 278443582
Change-Id: I7fc3a19932e60b235929edb6d46b20e0bda4903b

quic/test_tools/quic_dispatcher_peer.cc

diff --git a/quic/test_tools/quic_dispatcher_peer.cc b/quic/test_tools/quic_dispatcher_peer.cc
index 2590834..12c2b94 100644
--- a/quic/test_tools/quic_dispatcher_peer.cc
+++ b/quic/test_tools/quic_dispatcher_peer.cc
@@ -11,6 +11,12 @@
 namespace test {
 
 // static
+QuicTimeWaitListManager* QuicDispatcherPeer::GetTimeWaitListManager(
+    QuicDispatcher* dispatcher) {
+  return dispatcher->time_wait_list_manager_.get();
+}
+
+// static
 void QuicDispatcherPeer::SetTimeWaitListManager(
     QuicDispatcher* dispatcher,
     QuicTimeWaitListManager* time_wait_list_manager) {

quic/test_tools/quic_dispatcher_peer.h

diff --git a/quic/test_tools/quic_dispatcher_peer.h b/quic/test_tools/quic_dispatcher_peer.h
index a888b4e..7cb4c92 100644
--- a/quic/test_tools/quic_dispatcher_peer.h
+++ b/quic/test_tools/quic_dispatcher_peer.h
@@ -17,6 +17,9 @@
  public:
   QuicDispatcherPeer() = delete;
 
+  static QuicTimeWaitListManager* GetTimeWaitListManager(
+      QuicDispatcher* dispatcher);
+
   static void SetTimeWaitListManager(
       QuicDispatcher* dispatcher,
       QuicTimeWaitListManager* time_wait_list_manager);