QString::replace(pos, len, *unicode, size) can handle positions
which are outside of the this-string. In that case, it is a no-op.
Coverage analysis revealed we do not have a unit test for this.
This patch adds one.
Change-Id: Id4a407e860fff0d5c7c0a200c379e5e3961c86d2
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>
Reviewed-by: Jarek Kobus <jaroslaw.kobus@qt.io>