Fixes: NB#209217 - ARGB windows show up black in SB/x86 - refactor GLX config discovery so that we require working configs before   trying to use them - make sure we get the pixmap before painting also in custom TFP case
Fixes: NB#209217 - ARGB windows show up black in SB/x86
- refactor GLX config discovery so that we require working configs before
  trying to use them
- make sure we get the pixmap before painting also in custom TFP case

nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,siraj/mcompositor,nemomobile-graveyard/mcompositor,nemomobile-graveyard/mcompositor,siraj/mcompositor,nemomobile-graveyard/mcompositor,siraj/mcompositor,siraj/mcompositor