Log Message:
Fix PR #34087. Patch from Gilles Dauphin.

On Solaris 10, /usr/openwin/include/X11/Xutil.h does not include
Xlib.h.  It does have the comment:

  /* You must include <X11/Xlib.h> before including this file */

This means that Xlib.h doesn't pull in X.h and Pixmap and other
items are not defined.

With some other versions of X, the X11/Xutil.h header does include
X11/Xlib.h itself so this problem is not seen.