Attempt to extract this from bug 171667
Created attachment 311729 [details] Patch (WIP)
Comment on attachment 311729 [details] Patch (WIP) Attachment 311729 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: http://webkit-queues.webkit.org/results/3855104 New failing tests: compositing/iframes/scrolling-iframe.html
Created attachment 311742 [details] Archive of layout-test-results from ews123 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews123 Port: ios-simulator-wk2 Platform: Mac OS X 10.12.5
Created attachment 311819 [details] Patch (172851 + 172825)
Comment on attachment 311819 [details] Patch (172851 + 172825) Attachment 311819 [details] did not pass mac-ews (mac): Output: http://webkit-queues.webkit.org/results/3859695 New failing tests: fast/scrolling/scrolling-tree-includes-frame.html
Created attachment 311820 [details] Archive of layout-test-results from ews102 for mac-elcapitan The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews102 Port: mac-elcapitan Platform: Mac OS X 10.11.6
Comment on attachment 311819 [details] Patch (172851 + 172825) Attachment 311819 [details] did not pass mac-debug-ews (mac): Output: http://webkit-queues.webkit.org/results/3859713 New failing tests: fast/scrolling/scrolling-tree-includes-frame.html
Created attachment 311821 [details] Archive of layout-test-results from ews116 for mac-elcapitan The attached test failures were seen while running run-webkit-tests on the mac-debug-ews. Bot: ews116 Port: mac-elcapitan Platform: Mac OS X 10.11.6
Comment on attachment 311819 [details] Patch (172851 + 172825) Attachment 311819 [details] did not pass ios-sim-ews (ios-simulator-wk2): Output: http://webkit-queues.webkit.org/results/3859722 New failing tests: compositing/iframes/scrolling-iframe.html
Created attachment 311824 [details] Archive of layout-test-results from ews124 for ios-simulator-wk2 The attached test failures were seen while running run-webkit-tests on the ios-sim-ews. Bot: ews124 Port: ios-simulator-wk2 Platform: Mac OS X 10.12.5
Created attachment 311825 [details] Patch Simon: I'm not yet 100% sure of this on all these platforms and the patch applies on bug 172851 anyway, but I'm asking review to get some feedback.
Comment on attachment 311825 [details] Patch Attachment 311825 [details] did not pass mac-wk2-ews (mac-wk2): Output: http://webkit-queues.webkit.org/results/3860071 New failing tests: fast/scrolling/scrolling-tree-includes-frame.html
Created attachment 311829 [details] Archive of layout-test-results from ews104 for mac-elcapitan-wk2 The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews. Bot: ews104 Port: mac-elcapitan-wk2 Platform: Mac OS X 10.11.6
Created attachment 311842 [details] Patch Same patch, but try again after r217726.
Committed r217730: <http://trac.webkit.org/changeset/217730>