Per spec (http://dev.w3.org/csswg/css-sizing-3/#definite): "Additionally, the size of the containing block of an absolutely positioned element is always definite with respect to that element." If height is auto, we're ignoring this condition. Related Blink issue (where this was detected on flexbox first): https://codereview.chromium.org/1081433005/
Created attachment 251545 [details] Patch
Comment on attachment 251545 [details] Patch Clearing flags on attachment: 251545 Committed r183385: <http://trac.webkit.org/changeset/183385>
All reviewed patches have been landed. Closing bug.