glx: Suppress BadDrawable from DRI2CopyRegion

This can happen when an X window is destroyed behind our back.  We use
DRI2CopyRegion behind the scenes in many places (like flushing the fake
front to the real front) so we have to ignore X errors triggered in that
case.

The glean test cases trigger this consistently as they don't destroy the
GLX drawable nicely, they just destroy the X window.
1 file changed