Code review comment for lp:~smspillaz/compiz-core/compiz-core.work_923683

Tested this branch by itself and merged with lp:~smspillaz/compiz-core/compiz-core.fix_969108.2

By itself, this branch still makes window movement unacceptably slow. With the other branch designed to make movement more efficient, windows now often don't move at all when dragged.

Unfortunately performance is getting worse, not better.