Add test for css3 background size.
Add tests for css3 background clip.
Add tests for css3 background origin.
Add tests for css3 border image.
Add test for css3 background-clip.
Add test for css3 box-shadow.
Add test for css3 background-size.
Add test for css3 background-image: contain.
Add test for css3 transform: perspective.
Add test for css3 transform: rotate.
Add test for css3 transform: skewX.
Add test for css3 transform: skewY.
Add test for css3 transforms: rotate/translate/scale.
Add test for css3 transforms: rotateY.
Add test for css3 transform: scale.
Merging https://github.com/w3c/csswg-test/pull/77
Merging https://github.com/w3c/csswg-test/pull/81
Merging https://github.com/w3c/csswg-test/pull/82
Merging https://github.com/w3c/csswg-test/pull/83
Merging https://github.com/w3c/csswg-test/pull/84