Fix compiled Promise polyfill
Fix compiled Promise polyfill

Installation of the Promise polyfill was incomplete in compiled mode,
since static methods were not attached to the constructor by the
compiler.

Closes #236

Change-Id: I304662dfdb88d2fb76fc8c06a23fc6fae2f5b1f1

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