This piece is extracted from bug 171667, where we will need a separate layer for the scrollable frames. For now, we will only do that when ScrollingTreeIncludesFrames=true, so that we do not change the default behavior.
Created attachment 311809 [details] Patch
Comment on attachment 311809 [details] Patch Attachment 311809 [details] did not pass mac-ews (mac): Output: http://webkit-queues.webkit.org/results/3858870 New failing tests: compositing/iframes/compositing-for-scrollable-iframe.html
Created attachment 311813 [details] Archive of layout-test-results from ews103 for mac-elcapitan The attached test failures were seen while running run-webkit-tests on the mac-ews. Bot: ews103 Port: mac-elcapitan Platform: Mac OS X 10.11.6
Comment on attachment 311809 [details] Patch Attachment 311809 [details] did not pass mac-debug-ews (mac): Output: http://webkit-queues.webkit.org/results/3858895 New failing tests: compositing/iframes/compositing-for-scrollable-iframe.html
Created attachment 311816 [details] Archive of layout-test-results from ews113 for mac-elcapitan The attached test failures were seen while running run-webkit-tests on the mac-debug-ews. Bot: ews113 Port: mac-elcapitan Platform: Mac OS X 10.11.6
Created attachment 311817 [details] Patch
Comment on attachment 311817 [details] Patch View in context: https://bugs.webkit.org/attachment.cgi?id=311817&action=review > Source/WebKit2/WebProcess/WebCoreSupport/WebChromeClient.h:229 > + ScrollableInnerFrameTrigger | Maybe ScrollableNonMainFrameTrigger? I don't actually know if anyone uses these triggers any more, now that Blink is out of the repo.
Committed r217726: <http://trac.webkit.org/changeset/217726>
(In reply to Simon Fraser (smfr) from comment #7) > I don't actually know if anyone uses these triggers any more, now that Blink > is out of the repo. Yes, this is actually only used in RenderLayerCompositor::requiresCompositingForScrollableFrame ; I renamed the flag as you suggest.