Created attachment 216261[details]
Test to reproduce the problem in 4 steps
When a div with overflow: auto contains a child with position:absolute, the scroll bars are not always removed when they should be. If the overflow div shows scrollbars (for any reason) and the absolute div is moved (at least partly) outside the parent, the scrollbars will not be removed when the reason for scrollbars is removed and the absolute div is moved back to inside its parent.
Test case at http://artur.virtuallypreinstalled.com/webkit-scrollbars.html and as attachment.
Similar to #21462 and #71541 in the sense that scrollbars remain when they should not and in the sense that hacks to get around this become ugly and inefficient.
Created attachment 226390[details]
Archive of layout-test-results from webkit-ews-09 for mac-mountainlion-wk2
The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: webkit-ews-09 Port: mac-mountainlion-wk2 Platform: Mac OS X 10.8.5
Created attachment 226391[details]
Archive of layout-test-results from webkit-ews-03 for mac-mountainlion
The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: webkit-ews-03 Port: mac-mountainlion Platform: Mac OS X 10.8.5
Created attachment 226392[details]
Archive of layout-test-results from webkit-ews-04 for mac-mountainlion
The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: webkit-ews-04 Port: mac-mountainlion Platform: Mac OS X 10.8.5
Created attachment 226405[details]
Archive of layout-test-results from webkit-ews-13 for mac-mountainlion-wk2
The attached test failures were seen while running run-webkit-tests on the mac-wk2-ews.
Bot: webkit-ews-13 Port: mac-mountainlion-wk2 Platform: Mac OS X 10.8.5
Created attachment 226410[details]
Archive of layout-test-results from webkit-ews-08 for mac-mountainlion
The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: webkit-ews-08 Port: mac-mountainlion Platform: Mac OS X 10.8.5
Created attachment 226415[details]
Archive of layout-test-results from webkit-ews-02 for mac-mountainlion
The attached test failures were seen while running run-webkit-tests on the mac-ews.
Bot: webkit-ews-02 Port: mac-mountainlion Platform: Mac OS X 10.8.5
2013-11-06 22:53 PST, Artur Signell
2014-03-10 22:11 PDT, Manish Gurnaney
2014-03-10 23:13 PDT, Build Bot
2014-03-10 23:42 PDT, Build Bot
2014-03-10 23:45 PDT, Build Bot
2014-03-11 01:45 PDT, Manish Gurnaney
2014-03-11 02:43 PDT, Build Bot
2014-03-11 03:09 PDT, Build Bot
2014-03-11 03:54 PDT, Build Bot
2014-03-11 06:43 PDT, Manish Gurnaney
2014-03-11 22:42 PDT, Manish Gurnaney