Prior to this commit, when an unexpected pass occurred the test output
showed the message "XPASS : tst_foo::function() 'expr' returned FALSE",
where the problem was actually that the expression evaluated to true
when it was expected to be false.
This commit changes the output to make it clear that the expression
evaluated to true unexpectedly.
Task-number: QTBUG-22118
Change-Id: Id22c178073d3b75789675ca37a8ef019029b1f91
Reviewed-by: Rohan McGovern <rohan.mcgovern@nokia.com>