Add experimental option for TCP FastOpen....

net/socket/tcp_client_socket_libevent.h

Index: net/socket/tcp_client_socket_libevent.h
===================================================================
--- net/socket/tcp_client_socket_libevent.h	(revision 63182)
+++ net/socket/tcp_client_socket_libevent.h	(working copy)
@@ -43,6 +43,7 @@
   virtual void SetSubresourceSpeculation();
   virtual void SetOmniboxSpeculation();
   virtual bool WasEverUsed() const;
+  virtual bool UsingTCPFastOpen() const;
 
   // Socket methods:
   // Multiple outstanding requests are not supported.
@@ -127,6 +128,9 @@
   // Helper to add a TCP_CONNECT (end) event to the NetLog.
   void LogConnectCompletion(int net_error);
 
+  // Internal function to write to a socket.
+  int InternalWrite(IOBuffer* buf, int buf_len);
+
   int socket_;
 
   // The list of addresses we should try in order to establish a connection.
@@ -169,6 +173,12 @@
   // histograms.
   UseHistory use_history_;
 
+  // Enables experimental TCP FastOpen option.
+  bool use_tcp_fastopen_;
+
+  // True when TCP FastOpen is in use and we have done the connect.
+  bool tcp_fastopen_connected_;
+
   DISALLOW_COPY_AND_ASSIGN(TCPClientSocketLibevent);
 };