Code review comment for lp:~thomas-voss/mir/revert-process-group-leader-patch

oops...hit save too soon...
these are the 2 relevant competing bugs...
https://bugs.launchpad.net/xmir/+bug/1206508 "Xorg crash on xmir punts user back out to greeter" which is the ctl+c issue on sw rendering - which this mp was intending to fix

and https://bugs.launchpad.net/mir/+bug/1195509 "System compositor fails to start - Failed to set the current VT mode: Input/output error (5) " which is a infrequent occuring bug...and results in fall back, which is fixed by https://code.launchpad.net/~mlankhorst/mir/setsid/+merge/176676