This test performs a keyframed animation of the left property. It animates over 2 seconds. It takes 3 snapshots and expects each result to be within a specified range.
PASS - "left" property for "box" element at 0.4s saw something close to: 20
PASS - "left" property for "box" element at 1.2s saw something close to: 10
PASS - "left" property for "box" element at 1.6s saw something close to: 15