SSLClientSessionCache: Log number of times Lookup is called per Session.

net/socket/ssl_client_socket_impl.h

Index: net/socket/ssl_client_socket_impl.h
diff --git a/net/socket/ssl_client_socket_impl.h b/net/socket/ssl_client_socket_impl.h
index 4d44008cd7ff4e7090861b8f85547c9a95447311..ff30ccd715f44a23fc835c3a00ad0795f1cb52aa 100644
--- a/net/socket/ssl_client_socket_impl.h
+++ b/net/socket/ssl_client_socket_impl.h
@@ -315,6 +315,7 @@ class SSLClientSocketImpl : public SSLClientSocket,
   // session cache. i.e. sessions created with one value will not attempt to
   // resume on the socket with a different value.
   const std::string ssl_session_cache_shard_;
+  size_t ssl_session_cache_lookup_count_;
 
   enum State {
     STATE_NONE,