Improve QMenu autotest.

Improve QMenu autotest.

Originally this commit was just going to reinstate the disabled line of
test data (after correcting it to use keyboard modifiers instead of
invalid bitwise-or of key-codes, which would trigger an assert in
qtestlib).  Unfortunately, this revealed a minor bug in QMenu, as
reported in QTBUG-22449, so a QEXPECT_FAIL has also been added.

Change-Id: I29699fcbfa353c037a83379a6140f0e3da5be027
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>