QmlJS: Fix case-fallthrough.qml test

The warning about strange interactions between QtQuick1 and QtQuick2
doesn't exist anymore, and I don't see why it would show up in that case
anyway. QmlJS::StaticAnalysis::Type used to have a member 324, and the
comment references that.

Change-Id: I4f0a256588919a146068b8771954bcabf0468dbc
Reviewed-by: Marco Benelli <marco.benelli@qt.io>

tests/auto/qml/codemodel/check/case-fallthrough.qml

@@ -1,6 +1,6 @@
 import QtQuick 2.0
 
-Item { // 324 1 4
+Item {
     x: {
         switch (a) {
         case 1: