Add test to verify CastProxy includes every Player member.
Add test to verify CastProxy includes every Player member.

Issue #675

Change-Id: I0fe18ea28571ad2dd6c92587e5df345c80b223c6

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