[PATCH 00/19] glx: Various fixes

[Adam Jackson]

Mostly janitorial fixes to glx.  The GetDrawableAttributes parts are based
on an earlier patch series I'd sent, and do fix piglit tests.  The
previous series actually tracked GLX_PRESERVED_CONTENTS according to what
the client had set; this version just always returns TRUE as it's simpler.

I have a more invasive set of GLX changes I'd like to land later, I'd like
to get these more trivial bits out of the way first.

- ajax