Isolate Storage Remove Function
Isolate Storage Remove Function

Isolate the use of storage engine in the remove function so that it should
be easier to replace it with the new storage system.

Change-Id: Ia764b680026018dfcb10f8bebc98e4d7435793d8

TheModMaker/shaka-player,TheModMaker/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,TheModMaker/shaka-player,TheModMaker/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,shaka-project/shaka-player,tvoli/shaka-player,shaka-project/shaka-player,tvoli/shaka-player