Replace excessive usage of getBoundingClientRect #12109
Description
cc: @Cwiiis
Describe the Bug
getBoundingClientRect is a costly function, we should review it's usage so it doesn't trigger unwanted style-calculation or layouting in the browser. All usages possibly should happen inside LayoutingService task or Canvas drawing callback 0 to be scheduled in the animation frame where we have all elements in place.
This is optimization task, best to do a profiling before and after the change and upload image in the PR.
Examples where to look:
- HRuler, VRuler and scrolling the document
- other places https://github.com/search?q=repo%3ACollaboraOnline%2Fonline%20getBoundingClientRect&type=code