Fix #13561: gotoPercent has no effect on fx.chain

Corresponding Dojo ticket: https://bugs.dojotoolkit.org/ticket/13561

Fix for an animation chain's gotoPercent

* fix incorrect `this` reference in `some` callback
* reverse animation duration and offset check
* update the index to the current animation once found
* call gotoPercent on individual animation, but do not pass andPlay flag
* if andPlay, then call play on this chain