Server push cancellation: add a finch trial parameter

net/tools/quic/quic_simple_dispatcher.h

Index: net/tools/quic/quic_simple_dispatcher.h
diff --git a/net/tools/quic/quic_simple_dispatcher.h b/net/tools/quic/quic_simple_dispatcher.h
index b9df6d9c63cb92b82c793313f04109527b488cbb..41d24cfb33bbd5310efc07a664a026cf31aec4ac 100644
--- a/net/tools/quic/quic_simple_dispatcher.h
+++ b/net/tools/quic/quic_simple_dispatcher.h
@@ -24,6 +24,10 @@ class QuicSimpleDispatcher : public QuicDispatcher {
 
   ~QuicSimpleDispatcher() override;
 
+  int GetRstErrorCount(QuicRstStreamErrorCode rst_error_code) const;
+
+  void OnRstStreamReceived(const QuicRstStreamFrame& frame) override;
+
  protected:
   QuicServerSessionBase* CreateQuicSession(
       QuicConnectionId connection_id,
@@ -33,6 +37,9 @@ class QuicSimpleDispatcher : public QuicDispatcher {
 
  private:
   QuicHttpResponseCache* response_cache_;  // Unowned.
+
+  // The map of the reset error code with its counter.
+  std::map<QuicRstStreamErrorCode, int> rst_error_map_;
 };
 
 }  // namespace net