Fix bugs.webkit.org/show_bug.cgi?id=17001 (Build error with Gtk port on Mac OS X).
Reviewed by Darin Adler.
If both XP_MACOSX and XP_UNIX are defined then X11.h and Carbon.h will both be included.
These provide conflicting definitions for a type named 'Cursor'. As XP_UNIX is set by
the build system when targeting X11, it doesn't make sense for XP_MACOSX to also be set
in this instance.
* bindings/npapi.h: Don't define XP_MACOSX if XP_UNIX is defined.
git-svn-id: https://svn.webkit.org/repository/webkit/trunk@29806
268f45cc-cd09-0410-ab3c-
d52691b4dbfc