Notify NQE of TCP RTT values

net/socket/tcp_socket_posix.h

Index: net/socket/tcp_socket_posix.h
diff --git a/net/socket/tcp_socket_posix.h b/net/socket/tcp_socket_posix.h
index 98849e45a1918d1e34e1cbc550d18621e4f22d47..d092b572da72d4361c43be637a3ba176f6c25486 100644
--- a/net/socket/tcp_socket_posix.h
+++ b/net/socket/tcp_socket_posix.h
@@ -15,8 +15,13 @@
 #include "net/base/address_family.h"
 #include "net/base/completion_callback.h"
 #include "net/base/net_export.h"
+#include "net/base/socket_performance_watcher.h"
 #include "net/log/net_log.h"
 
+namespace base {
+class TickClock;
+}
+
 namespace net {
 
 class AddressList;
@@ -26,7 +31,12 @@ class SocketPosix;
 
 class NET_EXPORT TCPSocketPosix {
  public:
-  TCPSocketPosix(NetLog* net_log, const NetLog::Source& source);
+  // |socket_performance_watcher| is notified of the performance metrics related
+  // to this socket. |socket_performance_watcher| may be null.
+  TCPSocketPosix(
+      scoped_ptr<SocketPerformanceWatcher> socket_performance_watcher,
+      NetLog* net_log,
+      const NetLog::Source& source);
   virtual ~TCPSocketPosix();
 
   int Open(AddressFamily family);
@@ -95,6 +105,8 @@ class NET_EXPORT TCPSocketPosix {
   void StartLoggingMultipleConnectAttempts(const AddressList& addresses);
   void EndLoggingMultipleConnectAttempts(int net_error);
 
+  void SetTickClockForTesting(scoped_ptr<base::TickClock> tick_clock);
+
   const BoundNetLog& net_log() const { return net_log_; }
 
  private:
@@ -177,8 +189,8 @@ class NET_EXPORT TCPSocketPosix {
   int BuildTcpSocketPosix(scoped_ptr<TCPSocketPosix>* tcp_socket,
                           IPEndPoint* address);
 
-  void ConnectCompleted(const CompletionCallback& callback, int rv) const;
-  int HandleConnectCompleted(int rv) const;
+  void ConnectCompleted(const CompletionCallback& callback, int rv);
+  int HandleConnectCompleted(int rv);
   void LogConnectBegin(const AddressList& addresses) const;
   void LogConnectEnd(int net_error) const;
 
@@ -195,12 +207,30 @@ class NET_EXPORT TCPSocketPosix {
                        int buf_len,
                        const CompletionCallback& callback);
 
+  // Notifies |socket_performance_watcher_| of the latest RTT estimate available
+  // from the tcp_info struct for this TCP socket.
+  void NotifySocketPerformanceWatcher();
+
   // Called after the first read completes on a TCP FastOpen socket.
   void UpdateTCPFastOpenStatusAfterRead();
 
   scoped_ptr<SocketPosix> socket_;
   scoped_ptr<SocketPosix> accept_socket_;
 
+  // Socket performance statistics (such as RTT) are reported to the
+  // |socket_performance_watcher_|. May be nullptr.
+  scoped_ptr<SocketPerformanceWatcher> socket_performance_watcher_;
+
+  scoped_ptr<base::TickClock> tick_clock_;
+
+  // Minimum interval betweeen consecutive notifications to
+  // |socket_performance_watcher_|.
+  const base::TimeDelta rtt_notifications_minimum_interval_;
+
+  // Time when the |socket_performance_watcher_| was last notified of updated
+  // RTT.
+  base::TimeTicks last_rtt_notification_;
+
   // Enables experimental TCP FastOpen option.
   bool use_tcp_fastopen_;