Flow Update
Summary: Update Alpha Darken Composite Operation to use flow more reasonably
Forum thread: https://forum.kde.org/viewtopic.php?f=288&t=136165&sid=b0322cc336861566b625af479805062b
Reviewers: Krita, dkazakov!
Subscribers: rempt, woltherav, dkazakov, kamathraghavendra, Deevad, ramonmiranda, wbrown
Tags: Krita
Maniphest Tasks: T8576
Differential Revision: https://phabricator.kde.org/D18467