Add TRACE_EVENT macros to net.

net/socket/ssl_client_socket_openssl.cc

Index: net/socket/ssl_client_socket_openssl.cc
diff --git a/net/socket/ssl_client_socket_openssl.cc b/net/socket/ssl_client_socket_openssl.cc
index 76cf9b5b0154d6d08e37850f0183ef411a8bb008..a45653bd0183635e664a5730a0c31dde096860ef 100644
--- a/net/socket/ssl_client_socket_openssl.cc
+++ b/net/socket/ssl_client_socket_openssl.cc
@@ -30,6 +30,7 @@
 #include "base/strings/string_piece.h"
 #include "base/synchronization/lock.h"
 #include "base/threading/thread_local.h"
+#include "base/trace_event/trace_event.h"
 #include "base/values.h"
 #include "crypto/auto_cbb.h"
 #include "crypto/ec_private_key.h"
@@ -1474,6 +1475,7 @@ void SSLClientSocketOpenSSL::OnRecvComplete(int result) {
 }
 
 int SSLClientSocketOpenSSL::DoHandshakeLoop(int last_io_result) {
+  TRACE_EVENT0("net", "SSLClientSocketOpenSSL::DoHandshakeLoop");
   int rv = last_io_result;
   do {
     // Default to STATE_NONE for next state.