Instead of comparing to absolute values, compare the result from
QDeadlineTimer with the reference clock types from std::chrono. Pass
the test as long as we are within 10% of that reference.
In addition, handle the case where QTest::qSleep sleeps for more than
10% longer or shorter than what is requested, and if so, abort the
test.
Change-Id: If8b77aea55a8c5c53e96427b2fff2f78281d0f82
Reviewed-by: Lars Knoll <lars.knoll@qt.io>