Stefan Brüns authored Aug 21, 2020 and David Faure committed Aug 29, 2020

Commit 8ed64be9 ("Enlarge image in folder preview when there's only
one image") made createSubThumbnail part of drawSubThumbnail. As a side
effect, when skipValidItems is > 0, the thumbnail is not only fetched
but also drawn in the top left position.

Split fetching and drawing again.

This is visible in the file dialogs (dolphin only uses sequenceIndex==0),
when hovering a directory with the mouse.