Hedger Wang ae58fe221b Stop handling animation once Navigator is unmounted.
Summary: public
Navigator subscribes to its internal animation spring that may still
asks navigator to re-render after being unmounted.

This diff clears the listeners of its animation spring once navigator
is unmounted.

Reviewed By: zjj010104

Differential Revision: D2588434

fb-gh-sync-id: 2b3ee65d3a6c3d45e5c6904d1dc65ac5a3e4534a
2015-10-27 18:30:24 -07:00
..
2015-07-24 13:16:25 -08:00