Create an interface for explicit notification of Dispatcher about

net/quic/quic_session.cc

Index: net/quic/quic_session.cc
diff --git a/net/quic/quic_session.cc b/net/quic/quic_session.cc
index a981b5e8e9e6b42ee24cde40a5a5260a305f58b3..5ec68ee609050bab06774f8c6c901e95463d617a 100644
--- a/net/quic/quic_session.cc
+++ b/net/quic/quic_session.cc
@@ -64,12 +64,16 @@ class VisitorShim : public QuicConnectionVisitorInterface {
     session_->OnConfigNegotiated();
   }
 
-  virtual void OnConnectionClosed(QuicErrorCode error,
-                                  bool from_peer) OVERRIDE {
+  virtual void OnConnectionClosed(
+      QuicErrorCode error, bool from_peer) OVERRIDE {
     session_->OnConnectionClosed(error, from_peer);
     // The session will go away, so don't bother with cleanup.
   }
 
+  virtual void OnWriteBlocked() OVERRIDE {
+    session_->OnWriteBlocked();
+  }
+
   virtual bool HasPendingHandshake() const OVERRIDE {
     return session_->HasPendingHandshake();
   }