A lot of the W3C CSS Shapes tests fail because "" !=== null.
Check the expected results for FAIL entries.
We need to send a patch to W3C/CSS. My reading of the CSS OM specification says we are correct and the test is wrong.
Once that's confirmed and landed, re-import the W3C tests.
./Tools/Scripts/import-w3c-tests ../csswg-test/ -t css-shapes-1 -d imported/w3c/csswg-test/