Updated player pause/unpause test
Rewrote auto-test-start-iterations test for new behaviour
Remove player._unboundedCurrentTime logging from playground
Fix event current time bug on player
Fix polyfill to match spec's definition of the active phase for a timed item
Fix old use of player.paused assignment
Rebaseline expectations when modifying player source content
Fix old use of player.paused in test-repeated-pause
Fix incorrect reparenting of an animation in test-player and update expectations for new player API behaviour