The launcher is designed to exit as soon as possible
so there's no useless processes idling. Now when steam
launches blender with the launcher, this breaks the
time tracking steam has as the thing it just started
exits within milliseconds.
There already is some code in the launcher that makes
the launcher linger to support background mode. This
patch extends this a bit to also wait if the parent
process is steam.exe
Reviewed by: brecht lichtwerk dingto
Differential Revision: https://developer.blender.org/D16527
58795c6047