Rewrite asynchronous MCI_PLAY command handling in MCIAVI driver, make
it more responsive to commands in the MCI_MODE_PLAY state by checking
hStopEvent even if the time frame between frames has expired.

Fix wgl regression: test glx server version and extensions to use (and
not use glXQueryDrawable on older glx implementations).

bug in SHFileOperation.

Free thread data in DLL_THREAD_DETACH.

single check.

Fix the printf sign flags so that '+' doesn't always override ' '
space alone.  If they both appear, continue parsing and let '+' take
precedence.

parts of the returned context are valid.

Ensure that the cbStruct member of the ACMDRIVERDETAILS[AW] struct is
filled with a valid value before returning.
Fill the cbStruct member of the ACMDRIVERDETAILS[AW] before sending a
ACMDM_DRIVER_DETAILS message to an installed codec that might be a
native library: native ACM codecs expect cbStruct to be valid before
filling the rest of the struct with any data.

Improved bounds checking.

(reported by Vitaliy Margolen).