Follow-up CASSANDRA-12905: always return future on Keyspace.applyFuture
Follow-up CASSANDRA-12905: always return future on Keyspace.applyFuture

Before CASSANDRA-12905, applyFuture always returned a future, regardless of whether isDeferrable was set or not.
This behavior should be maintained for applyFuture calls or compatibility method
Keyspace.apply(mutation, writeCommitlog, updateIndexes, isClReplay, isDeferrable, future).

jrwest/cassandra,snazy/cassandra,aureagle/cassandra,thelastpickle/cassandra,mike-tr-adamson/cassandra,pauloricardomg/cassandra,ollie314/cassandra,Instagram/cassandra,mike-tr-adamson/cassandra,instaclustr/cassandra,stef1927/cassandra,tjake/cassandra,beobal/cassandra,josh-mckenzie/cassandra,aureagle/cassandra,michaelsembwever/cassandra,blerer/cassandra,szhou1234/cassandra,Jaumo/cassandra,tommystendahl/cassandra,clohfink/cassandra,jeffjirsa/cassandra,tjake/cassandra,hengxin/cassandra,driftx/cassandra,jeromatron/cassandra,clohfink/cassandra,hengxin/cassandra,instaclustr/cassandra,strapdata/cassandra,exoscale/cassandra,kgreav/cassandra,joesiewert/cassandra,kgreav/cassandra,spodkowinski/cassandra,ollie314/cassandra,yhnishi/cassandra,bdeggleston/cassandra,juiceblender/cassandra,cooldoger/cassandra,iamaleksey/cassandra,jeffjirsa/cassandra,ollie314/cassandra,josh-mckenzie/cassandra,jbellis/cassandra,michaelsembwever/cassandra,belliottsmith/cassandra,thelastpickle/cassandra,Jollyplum/cassandra,aweisberg/cassandra,tommystendahl/cassandra,aboudreault/cassandra,christian-esken/cassandra,michaelsembwever/cassandra,snazy/cassandra,kgreav/cassandra,yhnishi/cassandra,Instagram/cassandra,Jaumo/cassandra,Instagram/cassandra,Jollyplum/cassandra,jasonstack/cassandra,Instagram/cassandra,exoscale/cassandra,mkjellman/cassandra,mshuler/cassandra,tommystendahl/cassandra,josh-mckenzie/cassandra,tjake/cassandra,stef1927/cassandra,instaclustr/cassandra,jasonwee/cassandra,iamaleksey/cassandra,aweisberg/cassandra,stef1927/cassandra,aweisberg/cassandra,adejanovski/cassandra,belliottsmith/cassandra,driftx/cassandra,scylladb/scylla-tools-java,spodkowinski/cassandra,apache/cassandra,sedulam/CASSANDRA-12201,WorksApplications/cassandra,tommystendahl/cassandra,stef1927/cassandra,clohfink/cassandra,snazy/cassandra,thelastpickle/cassandra,jbellis/cassandra,jrwest/cassandra,instaclustr/cassandra,blerer/cassandra,chbatey/cassandra-1,beobal/cassandra,jasobrown/cassandra,DikangGu/cassandra,spodkowinski/cassandra,blerer/cassandra,szhou1234/cassandra,ifesdjeen/cassandra,yhnishi/cassandra,juiceblender/cassandra,scylladb/scylla-tools-java,aureagle/cassandra,blambov/cassandra,Jaumo/cassandra,jasonstack/cassandra,WorksApplications/cassandra,spodkowinski/cassandra,josh-mckenzie/cassandra,jasobrown/cassandra,bdeggleston/cassandra,szhou1234/cassandra,mshuler/cassandra,jrwest/cassandra,ifesdjeen/cassandra,jasobrown/cassandra,mkjellman/cassandra,sedulam/CASSANDRA-12201,blambov/cassandra,jrwest/cassandra,bcoverston/cassandra,mike-tr-adamson/cassandra,michaelsembwever/cassandra,chbatey/cassandra-1,mkjellman/cassandra,aboudreault/cassandra,apache/cassandra,mkjellman/cassandra,yukim/cassandra,krummas/cassandra,apache/cassandra,ptnapoleon/cassandra,tjake/cassandra,Jollyplum/cassandra,kgreav/cassandra,jeromatron/cassandra,blambov/cassandra,joesiewert/cassandra,ptnapoleon/cassandra,adejanovski/cassandra,DikangGu/cassandra,iamaleksey/cassandra,jasonwee/cassandra,ifesdjeen/cassandra,adelapena/cassandra,krummas/cassandra,jeffjirsa/cassandra,krummas/cassandra,jeromatron/cassandra,yukim/cassandra,thelastpickle/cassandra,exoscale/cassandra,aboudreault/cassandra,szhou1234/cassandra,apache/cassandra,scylladb/scylla-tools-java,WorksApplications/cassandra,strapdata/cassandra,cooldoger/cassandra,strapdata/cassandra,adelapena/cassandra,snazy/cassandra,hengxin/cassandra,blerer/cassandra,bcoverston/cassandra,cooldoger/cassandra,christian-esken/cassandra,WorksApplications/cassandra,jasonstack/cassandra,jeffjirsa/cassandra,ifesdjeen/cassandra,driftx/cassandra,adelapena/cassandra,yukim/cassandra,jasobrown/cassandra,bcoverston/cassandra,bdeggleston/cassandra,jasonwee/cassandra,clohfink/cassandra,bdeggleston/cassandra,mshuler/cassandra,strapdata/cassandra,christian-esken/cassandra,pauloricardomg/cassandra,mike-tr-adamson/cassandra,cooldoger/cassandra,mshuler/cassandra,juiceblender/cassandra,iamaleksey/cassandra,beobal/cassandra,pauloricardomg/cassandra,chbatey/cassandra-1,yukim/cassandra,blambov/cassandra,adejanovski/cassandra,pauloricardomg/cassandra,driftx/cassandra,belliottsmith/cassandra,bcoverston/cassandra,DikangGu/cassandra,belliottsmith/cassandra,adelapena/cassandra,juiceblender/cassandra,jbellis/cassandra,beobal/cassandra,krummas/cassandra,sedulam/CASSANDRA-12201,joesiewert/cassandra,scylladb/scylla-tools-java,ptnapoleon/cassandra,aweisberg/cassandra