Code review comment for lp:~vanvugt/mir/always-double-buffers

I tested full stack (backported to 0.11) and tested Ubuntu Touch proper on mako.

The bad news is I can now see stutters when crossing a screen boundary (multi-monitor with multiple display buffers historically needs triple or else the client starves). Also when entering and leaving bypass the transition is not seamless any more.

The worse news is I somehow made the server crash when testing this (invalid free) but can't reproduce it to debug.

Perhaps the ddouble branch still is the way forward. Either that or we need to examine our compositor/DB code to reduce buffer holding (stutters).