refactor: address review comments from #1401 (#1433)
refactor: address review comments from #1401 (#1433)

See: https://github.com/resin-io/etcher/pull/1401#pullrequestreview-37459059
Signed-off-by: Juan Cruz Viotti <4148f5869aa1bcd7efd85b513a5874967e585032@openmailbox.org>
resin-io/etcher,resin-io/herostratus,resin-io/resin-etcher,resin-io/herostratus,resin-io/etcher,resin-io/etcher,resin-io/etcher,resin-io/resin-etcher,resin-io/etcher