According to the 'Document Object Model' CSS spec: http://www.w3.org/TR/DOM-Level-2-Style/css.html Parameter 'pseudoElement' from function 'getComputedStyle' could be null. The GObject binding generator generates code that always check this parameter cannot be null.
Created attachment 204004 [details] Patch
Comment on attachment 204004 [details] Patch Looks good in general. It's a bit sad to duplicate some of the setup code but the existing one seems pretty specific to the test that uses it.
Comment on attachment 204004 [details] Patch Clearing flags on attachment: 204004 Committed r151489: <http://trac.webkit.org/changeset/151489>
All reviewed patches have been landed. Closing bug.