See https://github.com/whatwg/html/pull/4402 and tests at https://github.com/web-platform-tests/wpt/pull/15649 and https://github.com/web-platform-tests/wpt/pull/15649.
Created attachment 366222 [details] Patch
Created attachment 366237 [details] Patch
Comment on attachment 366237 [details] Patch Attachment 366237 [details] did not pass mac-ews (mac): Output: https://webkit-queues.webkit.org/results/11698318 New failing tests: imported/w3c/web-platform-tests/html/browsers/the-window-object/self-et-al.window.html
Created attachment 366242 [details] Archive of layout-test-results from ews103 for mac-highsierra The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews103 Port: mac-highsierra Platform: Mac OS X 10.13.6
Comment on attachment 366237 [details] Patch Attachment 366237 [details] did not pass mac-wk2-ews (mac-wk2): Output: https://webkit-queues.webkit.org/results/11698350 New failing tests: imported/w3c/web-platform-tests/html/browsers/the-window-object/self-et-al.window.html
Created attachment 366244 [details] Archive of layout-test-results from ews106 for mac-highsierra-wk2 The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews. Bot: ews106 Port: mac-highsierra-wk2 Platform: Mac OS X 10.13.6
Comment on attachment 366237 [details] Patch Attachment 366237 [details] did not pass mac-debug-ews (mac): Output: https://webkit-queues.webkit.org/results/11698400 New failing tests: imported/w3c/web-platform-tests/html/browsers/the-window-object/self-et-al.window.html
Created attachment 366248 [details] Archive of layout-test-results from ews114 for mac-highsierra The attached test failures were seen while running run-webkit-tests on the mac-debug-ews. Bot: ews114 Port: mac-highsierra Platform: Mac OS X 10.13.6
Comment on attachment 366237 [details] Patch Attachment 366237 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: https://webkit-queues.webkit.org/results/11698418 New failing tests: imported/w3c/web-platform-tests/html/browsers/the-window-object/self-et-al.window.html
Created attachment 366250 [details] Archive of layout-test-results from ews122 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews122 Port: ios-simulator-wk2 Platform: Mac OS X 10.13.6
Created attachment 366275 [details] Patch
Comment on attachment 366275 [details] Patch Clearing flags on attachment: 366275 Committed r243661: <https://trac.webkit.org/changeset/243661>
All reviewed patches have been landed. Closing bug.
<rdar://problem/49433379>