Summary:
Effects::checkInputWindowEvent(QWheelEvent *e) existed but it was not
hooked up to anything and would never be called.

This patch adds the relevant handling in the wayland filter, X filter so
the existing method gets called.

EffectQuickView is updated to handle wheel events.

Test Plan:
Used a ListView via an EffectQuickView in an effect.
I can now scroll with the mouse.

Reviewers: #kwin, zzag

Reviewed By: #kwin, zzag

Subscribers: zzag, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D25292