Adding instrumentation to locate the source of jankiness.

net/socket/tcp_client_socket.cc

 // Copyright (c) 2013 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/tcp_client_socket.h"
 
 #include "base/callback_helpers.h"
 #include "base/logging.h"
 #include "base/profiler/scoped_tracker.h"
 #include "net/base/io_buffer.h"
@@ skipping 309 matching lines @@
 }
 
 void TCPClientSocket::DidCompleteReadWrite(const CompletionCallback& callback,
                                            int result) {
   if (result > 0)
     use_history_.set_was_used_to_convey_data();
 
   // TODO(vadimt): Remove ScopedTracker below once crbug.com/418183 is fixed.
   tracked_objects::ScopedTracker tracking_profile(
       FROM_HERE_WITH_EXPLICIT_FUNCTION(
-          "TCPClientSocket::DidCompleteReadWrite"));
+          "418183 TCPClientSocket::DidCompleteReadWrite"));
   callback.Run(result);
 }
 
 int TCPClientSocket::OpenSocket(AddressFamily family) {
   DCHECK(!socket_->IsValid());
 
   int result = socket_->Open(family);
   if (result != OK)
     return result;
 
   socket_->SetDefaultOptionsForClient();
 
   return OK;
 }
 
 }  // namespace net