preconfigured extension manifest

browser/app/profile/extensions/Makefile.in

@@ -30,6 +30,8 @@ FILES := $(addprefix $(srcdir)/, $(FILES))
 
 libs::
 	$(INSTALL) $(FILES) $(DIST)/bin/defaults/profile/extensions
-
+	$(INSTALL) $(srcdir)/"installed-extensions.txt" $(DIST)/bin/Extensions
+ 
 install::
 	$(SYSINSTALL) $(IFLAGS1) $(FILES) $(DESTDIR)$(mozappdir)/defaults/profile/extensions
+	$(SYSINSTALL) $(IFLAGS1) $(srcdir)/"installed-extensions.txt" $(DESTDIR)$(mozappdir)/Extensions

browser/app/profile/extensions/installed-extensions.txt

@@ -0,0 +1,2 @@
+theme,{972ce4c6-7e08-4474-a285-3208198ce6fd}
+extension,{641d8d09-7dda-4850-8228-ac0ab65e2ac9}