Add a missing error check.

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@3002 d4fa192b-c00b-0410-8231-f00ffab90ce4

lib/libvcl/vcc_action.c

@@ -108,7 +108,11 @@ parse_error(struct tokenlist *tl)
 		vcc_NextToken(tl);
 	} else if (tl->t->tok == VAR) {
 		Fb(tl, 0, ", ");
-		vcc_StringVal(tl);
+		if (!vcc_StringVal(tl)) {
+			ERRCHK(tl);
+			vcc_ExpectedStringval(tl);
+			return;
+		}
 	} else {
 		Fb(tl, 0, ", (const char *)0");
 	}