Adapt test to QMetaMethod change

With the new compile time type registration, the type is no longer
unknown, causing the test to fail.
Until we decide exactly how to deal with unknown types in QML, leave the
test as is, but mark the failing comparison as an expected failure.

Change-Id: Iaa23f096f686399b7199541b390655142fc40a37
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

tests/auto/qml/qqmlecmascript/tst_qqmlecmascript.cpp

@@ -3943,6 +3943,7 @@ void tst_qqmlecmascript::signalWithUnknownTypes()
     othertype.value = 17;
     emit object->signalWithCompletelyUnknownType(othertype);
 
+    QEXPECT_FAIL("", "New metaobject implementation causes test to pass", Continue);
     QVERIFY(!object->variant().isValid());
 
     delete object;