Reduce the amount of objects that are compiled several times
Summary:
We build some objects several times which makes it uncomfortable to develop KWin
since every time we modify something a lot of things get rebuilt. This should
help a bit although it doesn't solve all the problems.
Test Plan: Builds, tests pass
Reviewers: KWin, zzag
Reviewed By: KWin, zzag
Subscribers: davidedmundson, zzag, anthonyfieroni, iasensio, kwin
Tags: KWin
Differential Revision: https://phabricator.kde.org/D28445