Files go in, a .apk file comes out. Effective testing depends
on the aapt tool being installed.
Change-Id: I10daaabe9090c10181d9a83b876a934d540023d3
Reviewed-on: https://go-review.googlesource.com/3049
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>
David Crawshaw