Remove VisitorShim and move shim behavior into QuicConnection. No

net/quic/quic_connection.h

Index: net/quic/quic_connection.h
diff --git a/net/quic/quic_connection.h b/net/quic/quic_connection.h
index f82d04af19cf45052788377b69ce58b087916bfa..e89afe0aaa46c5345f08070e537a3126d4c696d7 100644
--- a/net/quic/quic_connection.h
+++ b/net/quic/quic_connection.h
@@ -132,6 +132,11 @@ class NET_EXPORT_PRIVATE QuicConnectionVisitorInterface {
   // Called when the connection receives a packet from a migrated client.
   virtual void OnConnectionMigration() = 0;
 
+  // Called after OnStreamFrame, OnRstStream, OnGoAway, OnWindowUpdateFrame,
+  // OnBlockedFrame, and OnCanWrite to allow post-processing once the work has
+  // been done.
+  virtual void PostProcessAfterData() = 0;
+
   // Called to ask if the visitor wants to schedule write resumption as it both
   // has pending data to write, and is able to write (e.g. based on flow control
   // limits).