Add and apply patch to set visibility to default during inclusion of

pthread headers.  Fixes problem linking JS on FreeBSD 9.0-RC1.

3rdp/build/GNUmakefile

@@ -30,6 +30,7 @@ $(JSLIB_BUILD): $(3RDP_ROOT)$(DIRSEP)dist/libmozjs.tgz | $(JS_SRC) $(JS_IDIR)
 	@echo Creating $@ ...
 	$(QUIET)-rm -rf $(JS_SRC)/*
 	$(QUIET)tar -xzC $(JS_SRC) -f $(3RDPDISTDIR)$(DIRSEP)libmozjs.tgz
+	$(QUIET)patch -d $(JS_SRC) < jsnativestack.cpp.patch
 	-$(QUIET)cd $(JS_SRC)$(DIRSEP)js-1.8.5$(DIRSEP)js$(DIRSEP)src && autoconf-2.13
 	$(QUIET)cd $(JS_SRC)$(DIRSEP)js-1.8.5$(DIRSEP)js$(DIRSEP)src && ./configure $(JS_CONFIGURE_ARGS)
 	$(QUIET)$(MAKE) -C $(JS_SRC)$(DIRSEP)js-1.8.5$(DIRSEP)js$(DIRSEP)src

3rdp/build/jsnativestack.cpp.patch

+--- js-1.8.5/js/src/jsnativestack.cpp.orig	2011-11-01 00:58:59.000000000 -0700
++++ js-1.8.5/js/src/jsnativestack.cpp	2011-11-01 01:02:48.000000000 -0700
+@@ -48,11 +48,13 @@
+ # include <os2.h>
+ 
+ #elif defined(XP_MACOSX) || defined(DARWIN) || defined(XP_UNIX)
++# pragma GCC visibility push(default)
+ # include <pthread.h>
+ 
+ # if defined(__FreeBSD__)
+ #  include <pthread_np.h>
+ # endif
++# pragma GCC visibility pop
+ 
+ #else
+ # error "Unsupported platform"