[wayland] Make sure that only the fading popups effect animates outline
Summary:
Window open/close animation effects should not animate the outline
because the end result is a bit awkward.
Reviewers: KWin, davidedmundson
Reviewed By: KWin, davidedmundson
Subscribers: kwin
Tags: KWin
Differential Revision: https://phabricator.kde.org/D19886