[RenderScript] Add finalizer to support lib context.

Bug: 28347289

  - Adding finalizer to support lib context, avoiding leak of native
    memory.

Change-Id: Ica3fdbfe65c0c651877be4324d0cb95a7256f8d7
(cherry picked from commit c90157d08c02c2c255580485346fdeffdd6315cd)
1 file changed