Reland 54771 (and 54795) To enable TCP Preconnection by default...

net/socket/client_socket_handle.h

 // Copyright (c) 2010 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.
 
 #ifndef NET_SOCKET_CLIENT_SOCKET_HANDLE_H_
 #define NET_SOCKET_CLIENT_SOCKET_HANDLE_H_
 #pragma once
 
 #include <string>
 
@@ skipping 114 matching lines @@
     return ssl_error_response_info_;
   }
   ClientSocketHandle* release_pending_http_proxy_connection() {
     return pending_http_proxy_connection_.release();
   }
 
   // These may only be used if is_initialized() is true.
   const std::string& group_name() const { return group_name_; }
   int id() const { return pool_id_; }
   ClientSocket* socket() { return socket_.get(); }
-  ClientSocket* release_socket() { return socket_.release(); }
+  ClientSocket* release_socket() {
+    // Update the base class to record things like whether we've ever
+    // transmitted data, and whether the connection was able to be established.
+    // We use this data to construct histograms indicating whether a
+    // speculative connection was ever used, etc., when the ClientSocket is
+    // eventually discarded.
+    if (socket_.get())
+      socket_->UpdateConnectivityState(is_reused());
+    return socket_.release();
+  }
   bool is_reused() const { return is_reused_; }
   base::TimeDelta idle_time() const { return idle_time_; }
   SocketReuseType reuse_type() const {
     if (is_reused()) {
       return REUSED_IDLE;
     } else if (idle_time() == base::TimeDelta()) {
       return UNUSED;
     } else {
       return UNUSED_IDLE;
     }
@@ skipping 74 matching lines @@
     user_callback_ = callback;
   } else {
     HandleInitCompletion(rv);
   }
   return rv;
 }
 
 }  // namespace net
 
 #endif  // NET_SOCKET_CLIENT_SOCKET_HANDLE_H_