Implement QuicChannel and QuicChannelFactory

net/quic/p2p/quic_p2p_session.cc

Index: net/quic/p2p/quic_p2p_session.cc
diff --git a/net/quic/p2p/quic_p2p_session.cc b/net/quic/p2p/quic_p2p_session.cc
index bd8f1c3e37e7878e6e78855ef529da48569a05ae..c8cc5819c0c4dfcff736591838dd526e8ce4d6eb 100644
--- a/net/quic/p2p/quic_p2p_session.cc
+++ b/net/quic/p2p/quic_p2p_session.cc
@@ -67,6 +67,8 @@ QuicP2PStream* QuicP2PSession::CreateOutgoingDynamicStream() {
 void QuicP2PSession::OnConnectionClosed(QuicErrorCode error, bool from_peer) {
   QuicSession::OnConnectionClosed(error, from_peer);
 
+  socket_.reset();
+
   if (delegate_) {
     Delegate* delegate = delegate_;
     delegate_ = nullptr;
@@ -98,6 +100,10 @@ int QuicP2PSession::DoRead() {
   DCHECK_EQ(read_state_, READ_STATE_DO_READ);
   read_state_ = READ_STATE_DO_READ_COMPLETE;
 
+  if (!socket_) {
+    return net::ERR_SOCKET_NOT_CONNECTED;
+  }
+
   return socket_->Read(
       read_buffer_.get(), kMaxPacketSize,
       base::Bind(&QuicP2PSession::DoReadLoop, base::Unretained(this)));