AAPT2: Set compatible-screens in manifest for multi-APK

If an artifact in a multi-apk set is for a scpecific set of screen
densities then update the manifest to set the compatible-screens element
to match.

Test: ran unit tests
Test: manually ran optimize command

Change-Id: I07e90850ab2f4647a8623acbeaccbebbe81c3a6a
1 file changed