Add TRACE_EVENT macros to net.

net/socket/client_socket_pool_base.cc

Index: net/socket/client_socket_pool_base.cc
diff --git a/net/socket/client_socket_pool_base.cc b/net/socket/client_socket_pool_base.cc
index e92594375d291b9f92be2c7b042ed61b08a53375..b240e3db0269255ff31013a665f5d945a67d4ccd 100644
--- a/net/socket/client_socket_pool_base.cc
+++ b/net/socket/client_socket_pool_base.cc
@@ -16,6 +16,7 @@
 #include "base/strings/string_util.h"
 #include "base/thread_task_runner_handle.h"
 #include "base/time/time.h"
+#include "base/trace_event/trace_event.h"
 #include "base/values.h"
 #include "net/base/net_errors.h"
 #include "net/log/net_log.h"
@@ -104,6 +105,7 @@ void ConnectJob::SetSocket(scoped_ptr<StreamSocket> socket) {
 }
 
 void ConnectJob::NotifyDelegateOfCompletion(int rv) {
+  TRACE_EVENT0("net", "ConnectJob::NotifyDelegateOfCompletion");
   // The delegate will own |this|.
   Delegate* delegate = delegate_;
   delegate_ = NULL;