Diffusion KWin cd99a901f601

[effects/presentwindows] Port present windows to EffectQuickView

Authored by davidedmundson on Oct 21 2019, 1:36 PM.

Description

[effects/presentwindows] Port present windows to EffectQuickView

Summary:
Removes over 100 lines of rather confusing code, implicitly introduces a
sharedEngine. Doesn't perform hide/show by moving a window offscreen.

As for the freeze, proving that EffectQuickView covers this case without
lots of extra C++ is an important pre-requisite for ever moving this
effect to a magic declarative API.

General code structure remains the same.

Test Plan: Opened present windows

Reviewers: KWin, zzag

Reviewed By: KWin, zzag

Subscribers: zzag, kwin

Tags: KWin

Differential Revision: https://phabricator.kde.org/D24240