chromium/third_party/blink/web_tests/transitions/mask-transitions-expected.txt

PASS - "-webkit-mask-position-x" property for "box" element at 0.5s saw something close to: 10
PASS - "-webkit-mask-position-y" property for "box" element at 0.5s saw something close to: 10
PASS - "-webkit-mask-size" property for "box2" element at 0.5s saw something close to: 150,150