Fix Promise-related failures on Edge
Fix Promise-related failures on Edge

This is a bad interaction between Jasmine's mock clock and Edge's
Promise implementation.  It was discovered while focusing a test
suite that uses mock clock.

This problem should not affect the library.

Change-Id: I36e008a49a5190c7c12416deabfba4dd43abe7da

cmgrecu/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,TheModMaker/shaka-player,russitto/shaka-player,ustudio/shaka-player,indiereign/shaka-player,indiereign/shaka-player,Ross-cz/shaka-player,baconz/shaka-player,vimond/shaka-player,cmgrecu/shaka-player,shaka-project/shaka-player,TobbeEdgeware/shaka-player,Ross-cz/shaka-player,TobbeEdgeware/shaka-player,shaka-project/shaka-player,brightcove/shaka-player,TheModMaker/shaka-player,TheModMaker/shaka-player,ustudio/shaka-player,TheModMaker/shaka-player,brightcove/shaka-player,tvoli/shaka-player,indiereign/shaka-player,russitto/shaka-player,Ross-cz/shaka-player,vimond/shaka-player,tvoli/shaka-player,baconz/shaka-player,TobbeEdgeware/shaka-player,russitto/shaka-player,brightcove/shaka-player,ustudio/shaka-player,vimond/shaka-player,ustudio/shaka-player,baconz/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,cmgrecu/shaka-player