After r267688, many compositing tests are timing out in the GTK bots, likely due to missing either the isolatedUpdateRendering() call or calling finalizeRenderingUpdate() in some CoordinatedGraphics classes. Patch in the works. Sample test run: https://build.webkit.org/results/GTK%20Linux%2064-bit%20Release%20(Tests)/r267688%20(16088)/results.html
Created attachment 409866 [details] Patch
Comment on attachment 409866 [details] Patch cq+ 'ing as the failure does not seems to be related to the patch.
Committed r267691: <https://trac.webkit.org/changeset/267691> All reviewed patches have been landed. Closing bug and clearing flags on attachment 409866 [details].
<rdar://problem/69677415>
Thanks for the fix!