Fix for Unix build bustage. We only build the editor core code if

MOZ_EDITOR is set, otherwise, we just export the editor interfaces.

editor/Makefile.in

@@ -22,11 +22,14 @@ srcdir		= @srcdir@
 
 include $(DEPTH)/config/autoconf.mk
 
-DIRS = public core
+DIRS = public
 
+ifdef MOZ_EDITOR
+DIRS += core
 ifdef ENABLE_TESTS
 DIRS += tests
 endif
+endif
 
 include $(topsrcdir)/config/config.mk