WebProcessPool::screenPropertiesStateChanged() duplicates some code that's done in displayReconfigurationCallBack() so clean that up.
<rdar://problem/104719183>
Pull request: https://github.com/WebKit/WebKit/pull/9195
Committed 259495@main (51bff517ffd1): <https://commits.webkit.org/259495@main> Reviewed commits have been landed. Closing PR #9195 and removing active labels.