[KIconLoader] Take into account devicePixelRatio for overlays

Authored by broulik on Feb 15 2018, 12:47 PM.

Description

[KIconLoader] Take into account devicePixelRatio for overlays

Keeps them from being painted outside view and scales them with the image they're supposed to be painted on.

Differential Revision: https://phabricator.kde.org/D9814