Plumbing for TCP FastOpen for SSL sockets.

net/socket/ssl_client_socket_pool.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "net/socket/ssl_client_socket_pool.h"
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram.h"
@@ skipping 289 matching lines @@
   return rv;
 }
 
 int SSLConnectJob::DoTransportConnect() {
   DCHECK(transport_pool_);
 
   next_state_ = STATE_TRANSPORT_CONNECT_COMPLETE;
   transport_socket_handle_.reset(new ClientSocketHandle());
   scoped_refptr<TransportSocketParams> direct_params =
       params_->GetDirectConnectionParams();
+  // Enable TCP FastOpen for SSL socket.
+  // TODO (jri): Finch trial this.
+  direct_params->enable_use_tcp_fastopen();

[mmenke, 2014/08/13 15:03:07]

Hrm...It looks like nothing else modifies these params after construction. 
Given that they're refcounted as well, that makes me a little nervous.  It's
theoretically possible for the same params to be used for multiple calls to this
(Does it happen?  Maybe with multiple preconnects?  Which will still work, but
that makes me nervouse).

I see two ways around this:  Create a new params object here, or move this logic
into net/socket/client_socket_pool_manager.cc.  The latter may be the better
option - that's where we create the parameters in the first place, though it is
rather a mess.

[Jana, 2014/08/14 06:35:31]

I see... I understand, and I agree. I've modified client_socket_pool_manager to
do this with a new TransportSocketParams object -- PTAL. I would appreciate a
careful read of that code... I don't think I'm breaking anything but a couple of
more pairs of eyes are definitely helpful!

   return transport_socket_handle_->Init(group_name(),
                                         direct_params,
                                         priority(),
                                         io_callback_,
                                         transport_pool_,
                                         net_log());
 }
 
 int SSLConnectJob::DoTransportConnectComplete(int result) {
   if (result == OK)
@@ skipping 500 matching lines @@
   if (base_.CloseOneIdleSocket())
     return true;
   return base_.CloseOneIdleConnectionInHigherLayeredPool();
 }
 
 void SSLClientSocketPool::OnSSLConfigChanged() {
   FlushWithError(ERR_NETWORK_CHANGED);
 }
 
 }  // namespace net