Revert "clean up positional arguments"

This reverts commit 26420533.

The desired "%" are not in format strings, so they shouldn't be doubled.
Now that aapt is fixed to allow unformatted string-arrays, we can go
back to the correct single "%".

Change-Id: I83e58e3d3a4c1eb91ecaad3dc690c81d62aa17ff