Commit 6cee204d56 introduced overloads
of lastIndexOf() which drop the 'from' argument, inadvertently fixing
QTBUG-80694, but failed to provide the new overloads for all existing
lastIndexOf() overloads, making the fix for QTBUG-80694 incomplete.
This patch completes the fix, by adding the missing overloads (for
char-likes) and also adds the missing (non-regex) tests to
tst_qstringapisymmetry.
Also amends 1c164ec7f2.
Fixes: QTBUG-80694
Change-Id: Ib4b3d597d658ce2edf01a2bce0d711ecea593d6e
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>
ecc307ff41