Adding instrumentation to locate the source of jankiness.

net/socket/ssl_client_socket_nss.cc

Index: net/socket/ssl_client_socket_nss.cc
diff --git a/net/socket/ssl_client_socket_nss.cc b/net/socket/ssl_client_socket_nss.cc
index d336350f68d44a15502cd25705459bbdf3192c58..9f58551dbf78ad4667c72088ba32b0d1fb4d92d9 100644
--- a/net/socket/ssl_client_socket_nss.cc
+++ b/net/socket/ssl_client_socket_nss.cc
@@ -1631,6 +1631,11 @@ void SSLClientSocketNSS::Core::HandshakeCallback(
 }
 
 void SSLClientSocketNSS::Core::HandshakeSucceeded() {
+  // TODO(vadimt): Remove ScopedProfile below once crbug.com/424386 is fixed.
+  tracked_objects::ScopedProfile tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "424386 SSLClientSocketNSS::Core::HandshakeSucceeded"));
+
   DCHECK(OnNSSTaskRunner());
 
   PRBool last_handshake_resumed;
@@ -1657,6 +1662,11 @@ void SSLClientSocketNSS::Core::HandshakeSucceeded() {
 }
 
 int SSLClientSocketNSS::Core::HandleNSSError(PRErrorCode nss_error) {
+  // TODO(vadimt): Remove ScopedProfile below once crbug.com/424386 is fixed.
+  tracked_objects::ScopedProfile tracking_profile(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "424386 SSLClientSocketNSS::Core::HandleNSSError"));
+
   DCHECK(OnNSSTaskRunner());
 
   int net_error = MapNSSClientError(nss_error);
@@ -1804,6 +1814,11 @@ int SSLClientSocketNSS::Core::DoHandshake() {
   int net_error = OK;
   SECStatus rv = SSL_ForceHandshake(nss_fd_);
 
+  // TODO(vadimt): Remove ScopedProfile below once crbug.com/424386 is fixed.
+  tracked_objects::ScopedProfile tracking_profile1(
+      FROM_HERE_WITH_EXPLICIT_FUNCTION(
+          "424386 SSLClientSocketNSS::Core::DoHandshake 1"));
+
   // Note: this function may be called multiple times during the handshake, so
   // even though channel id and client auth are separate else cases, they can
   // both be used during a single SSL handshake.