Re: Sv: Sv: Sv: Support for background transparency

[Håkon Flatval]

I have tested building without Cairo after rebasing to the latest
master. It works well now, I can't see any artifacts.

I had less luck with the LUCID build, though. Running with
`./src/emacs -q -xrm 'Emacs.synchronous: true'` opens Emacs which
immediately freezes completely with a blank screen. I have waited
for several minutes with no reaction. Running the same command with
a normal GTK build worksfine.

I'm not sure how to address this. Unless you have ideas on how to
investigate this further, I propose keeping the preprocessor `#if`
clause to avoid 32-bit visuals for non-GTK builds.

- Håkon