Server push cancellation: add a finch trial parameter

net/tools/quic/quic_dispatcher.h

Index: net/tools/quic/quic_dispatcher.h
diff --git a/net/tools/quic/quic_dispatcher.h b/net/tools/quic/quic_dispatcher.h
index 266e3e458b747ddad730eb2bcab75469c97c97e2..a95fd8abb2cad1e42c1fef6e55ffe79620831ff1 100644
--- a/net/tools/quic/quic_dispatcher.h
+++ b/net/tools/quic/quic_dispatcher.h
@@ -85,6 +85,11 @@ class QuicDispatcher : public QuicTimeWaitListManager::Visitor,
   // Queues the blocked writer for later resumption.
   void OnWriteBlocked(QuicBlockedWriterInterface* blocked_writer) override;
 
+  // QuicSession::Visitor interface implementation (via inheritance of
+  // QuicTimeWaitListManager::Visitor):
+  // Collects reset error code received on streams.
+  void OnRstStreamReceived(const QuicRstStreamFrame& frame) override;
+
   // QuicTimeWaitListManager::Visitor interface implementation
   // Called whenever the time wait list manager adds a new connection to the
   // time-wait list.