Change use of stub! to stub

The `stub!` method is deprecated. Change all uses of it to `stub`.

Change-Id: I7dcd6578714af9b67aaa84eb3bad9d298d11702f
Reviewed-on: http://gerrit.causes.com/37002
Reviewed-by: Shane da Silva <shane@causes.com>
Tested-by: Shane da Silva <shane@causes.com>