Workaround for open source drivers.

Workaround for open source drivers.

On current open source drivers (1.9.2.901 intel and radeon pulled from X-edgers PPA), glXGetFBConfigFromVisualSGIX is not working as expected even though glxinfo lists GLX_SGIX_fbconfig as a supported extension. Rather than abort when this function fails, this simple patch tries the second code path provided when glXGetFBConfigFromVisualSGIX is unsupported.

BUG=none
TEST=by hand on Linux with 3D CSS

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=84653

[jonathan.backer, 2011-05-09 15:26:43]

FWIW, the buggy drivers for which this code works around are blacklisted.
However, the workaround seems safe, so I think it is worth including.

[apatrick_chromium, 2011-05-09 18:19:05]

LGTM