When a preferred density is supplied, the closest matching densities
will be selected, the rest stripped from the APK.
Split support will be enabled in a later CL. Command line support is still
needed, but the foundation is ready.
Bug:25958912
Change-Id: I56d599806b4ec4ffa24e17aad48d47130ca05c08
An early refactor. Some ideas became clearer as
development continued. Now the various phases are much
clearer and more easily reusable.
Also added a ton of tests!
Change-Id: Ic8f0a70c8222370352e63533b329c40457c0903e