Use the location where FileDescriptorWatcher is created to track the libevent handlers

net/socket/socket_posix.cc

 // Copyright 2014 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/socket_posix.h"
 
 #include <errno.h>
 #include <netinet/in.h>
 #include <sys/socket.h>
 #include <utility>
@@ skipping 42 matching lines @@
         return ERR_CONNECTION_FAILED;  // More specific than ERR_FAILED.
       return net_error;
     }
   }
 }
 
 }  // namespace
 
 SocketPosix::SocketPosix()
     : socket_fd_(kInvalidSocket),
+      accept_socket_watcher_(FROM_HERE),
+      read_socket_watcher_(FROM_HERE),
       read_buf_len_(0),
+      write_socket_watcher_(FROM_HERE),
       write_buf_len_(0),
       waiting_connect_(false) {}
 
 SocketPosix::~SocketPosix() {
   Close();
 }
 
 int SocketPosix::Open(int address_family) {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK_EQ(kInvalidSocket, socket_fd_);
@@ skipping 436 matching lines @@
     write_buf_ = NULL;
     write_buf_len_ = 0;
     write_callback_.Reset();
   }
 
   waiting_connect_ = false;
   peer_address_.reset();
 }
 
 }  // namespace net