The QScopedPointer::take() call in comparison() test was used to
avoid a double-deletion error, because the test is creating two
QScopedPointer instances referencing the same memory.
Avoid the take() call by providing a custom DummyDeleter and
managing the memory by the extarnal std::unique_ptr.
As the test now has no test-cases for QScopedPointer::take()
calls, create a new test for this deprecated API, and guard
it with QT_DEPRECATED_SINCE checks.
Task-number: QTBUG-104858
Change-Id: Iecc28d44d76c9ce5835e6b1a1df7db30e2a9ca25
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>