gui: Ensure all Retracer::Retracer members are initialized.
gui: Ensure all Retracer::Retracer members are initialized.

I was randomly getting some runs with core profile.

swq0553/apitrace,EoD/apitrace,apitrace/apitrace,schulmar/apitrace,EoD/apitrace,schulmar/apitrace,surround-io/apitrace,tuanthng/apitrace,surround-io/apitrace,swq0553/apitrace,joshua5201/apitrace,apitrace/apitrace,joshua5201/apitrace,schulmar/apitrace,trtt/apitrace,swq0553/apitrace,trtt/apitrace,trtt/apitrace,joshua5201/apitrace,apitrace/apitrace,trtt/apitrace,tuanthng/apitrace,tuanthng/apitrace,surround-io/apitrace,surround-io/apitrace,schulmar/apitrace,EoD/apitrace,joshua5201/apitrace,EoD/apitrace,surround-io/apitrace,trtt/apitrace,swq0553/apitrace,joshua5201/apitrace,tuanthng/apitrace,EoD/apitrace,apitrace/apitrace,tuanthng/apitrace,swq0553/apitrace,schulmar/apitrace