[mtiLib] Parse lookup-flags earlier

Such that we set them even if lookup block is empty.

Lib/fontTools/mtiLib/__init__.py

@@ -802,11 +802,11 @@ def parseLookup(lines, tableTag, font, lookupMap=None):
 	_, name, typ = line
 	log.debug("Parsing lookup type %s %s", typ, name)
 	lookup = ot.Lookup()
-	with lines.until('lookup end'):
-
 	lookup.LookupFlag,filterset = parseLookupFlags(lines)
 	if filterset is not None:
 		lookup.MarkFilteringSet = filterset
+	with lines.until('lookup end'):
+
 		lookup.LookupType, parseLookupSubTable = {
 			'GSUB': {
 				'single':	(0,	parseSingleSubst),