valgrind run results: initialize probe_socket_ in ctor.
valgrind run results: initialize probe_socket_ in ctor.

blu3sh3ll/slowhttptest,drat/slowhttptest,drat/slowhttptest,michalkoczwara/slowhttptest,erikdejonge/slowhttptest,michalkoczwara/slowhttptest,erikdejonge/slowhttptest,rodrigoac/slowhttptest,shekyan/slowhttptest,rodrigoac/slowhttptest,blu3sh3ll/slowhttptest,shekyan/slowhttptest