In Bug 184337 I started caching the state of CGDisplayUsesInvertedPolarity (and other accessibility settings) so that we could message them from the UIProcess, and avoid interacting with the Window Server in the WebContent process. Unfortunately, this caused certain accessibility features (such as inverted colors) to only be read when the UIProcess launched, because WebKit was not registered to be notified when screen-affecting accessibility changes were made. Instead, WebKit needs to register to be notified if accessibility preferences change so that it can notify the related WebContent processes that their screen characteristics may have changed.
<rdar://problem/39627764>
Created attachment 340099 [details] Patch
Created attachment 340104 [details] Patch for landing
Comment on attachment 340104 [details] Patch for landing Clearing flags on attachment: 340104 Committed r231648: <https://trac.webkit.org/changeset/231648>
All reviewed patches have been landed. Closing bug.