Based on a patch by Martin Kretzschmar; #122448

Based on a patch by Martin Kretzschmar; #122448

2003-12-02  Michael Meeks  <michael@ximian.com>

	Based on a patch by Martin Kretzschmar; #122448

	* gdk/gdk.h: new gdk_threads_lock, gdk_threads_unlock, point to
	implementation of GDK_THREADS_ENTER / GDK_THREADS_LEAVE.
	(GDK_THREADS_ENTER, GDK_THREADS_LEAVE): use gdk_threads_[un]lock
	function pointers. Deprecate the global gdk_threads_mutex variable.

	* gdk/gdk.c (gdk_threads_impl_lock, gdk_threads_impl_unlock): new,
	extracted from GTK_THREADS_ENTER/LEAVE macros.
	(gdk_threads_init): init gtk_threads_[un]lock if not set.
	(gdk_threads_set_lock_functions): impl.

	* gdk/gdkglobals.c: add definitions of gdk_threads_[un]lock.