Which dramatically speeds up switching between sheets in the referenced document. The problem here is that we have a timer for each buffered primitive. And we have a lot of primitives here. And the TimerManager does not scale well to lots and lots of timer, because it uses a linked list. So this change modifies the flushing mechanism, trading off some precision for some speed. Change-Id: I66a744f06af9b08d4e9b797d11db8d22f4060789 Reviewed-on: https://gerrit.libreoffice.org/c/core/+/182876 Tested-by: Jenkins Reviewed-by: Noel Grandin <noel.grandin@collabora.co.uk>