The introduction of begin()/end() actually made most tests
that still use rects() duplicates. Keep them, though, for
test coverage (rects() takes a very different code path
from begin()/end()), but, under the assumption that Qt at
some point will default to built with deprecated APIs dis-
abled, make the test compile with disabled deprecated API.
Port some checks that still used rects() to begin()/end().
Change-Id: Ia7da80f0cd6ef69693f54a474924683624a2c3eb
Reviewed-by: Lars Knoll <lars.knoll@qt.io>