refactor(groupBy-spec): no getUnsubscriptionFrame()
refactor(groupBy-spec): no getUnsubscriptionFrame()

Replace TestScheduler.getUnsubscriptionFrame() with
TestScheduler.parseMarblesAsSubscription().unsubscribedFrame. The former
should be deprecated.

gluck/RxJS,adrianomelo/RxJSNext,SangKa/RxJS-Docs-CN,elliotschi/rxjs,Igorbek/rxjs5,jayphelps/rxjs,figueredo/RxJS,staltz/RxJSNext,saneyuki/RxJS,adrianomelo/RxJSNext,robwormald/RxJS,RxJS-CN/RxJS-Docs-CN,elliotschi/rxjs,benlesh/RxJS,jadbox/RxJS,jinroh/RxJS,SangKa/RxJS-Docs-CN,staltz/RxJSNext,gluck/RxJS,adrianomelo/RxJSNext,martinsik/rxjs,robwormald/RxJS,IgorMinar/RxJS,adrianomelo/RxJS-1,benlesh/RxJS,mattpodwysocki/RxJS,Brocco/RxJS,Brocco/RxJS,trxcllnt/RxJS,gluck/RxJS,Igorbek/rxjs5,adrianomelo/RxJS-1,justinwoo/RxJS,staltz/RxJSNext,ReactiveX/rxjs,Brocco/RxJS,ReactiveX/RxJS,elliotschi/rxjs,jayphelps/rxjs,ReactiveX/rxjs,kwonoj/RxJS,jadbox/RxJS,mattpodwysocki/RxJS,Igorbek/rxjs5,adrianomelo/RxJS-1,martinsik/rxjs,figueredo/RxJS,jinroh/RxJS,figueredo/RxJS,jayphelps/rxjs,benlesh/RxJS,mattpodwysocki/RxJS,elliotschi/rxjs,jinroh/RxJS,SangKa/RxJS-Docs-CN,ReactiveX/rxjs,adrianomelo/RxJS-1,justinwoo/RxJS,trxcllnt/RxJS,RxJS-CN/RxJS-Docs-CN,jadbox/RxJS,martinsik/rxjs,Igorbek/rxjs5,benlesh/RxJS,trxcllnt/RxJS,IgorMinar/RxJS,ReactiveX/RxJS,jinroh/RxJS,jayphelps/rxjs,jayphelps/rxjs,figueredo/RxJS,justinwoo/RxJS,ReactiveX/RxJS,gluck/RxJS,martinsik/rxjs,kwonoj/RxJS,RxJS-CN/RxJS-Docs-CN,adrianomelo/RxJSNext,jadbox/RxJS,robwormald/RxJS,mattpodwysocki/RxJS,justinwoo/RxJS,ReactiveX/RxJS,trxcllnt/RxJS,saneyuki/RxJS,ReactiveX/rxjs,Brocco/RxJS,RxJS-CN/RxJS-Docs-CN,SangKa/RxJS-Docs-CN,robwormald/RxJS,staltz/RxJSNext,kwonoj/RxJS,kwonoj/RxJS