qt: do not use `RoundImage` when rounding is not wanted
Also fixes the regressions #28751 (closed), #28750 (closed), #28753 (closed), #28754 (closed) and #28749 (closed) that are introduced by !5864 (merged).
Close #28751 (closed). Close #28750 (closed). Close #28749 (closed). Close #28753 (closed). Close #28754 (closed).
Edited by Fatih Uzunoğlu