Remove PackageInfoWithoutStateUtils

Now that parsing is entirely server side, there is no point in having
the utilities and interfaces split between with and without state.

This merges the without state implementation down into the with state
variant to consolidate the code and remove unused code paths.

Test: atest CompatibilityModeTest
Test: atest PackageParserLegacyCoreTest
Test: atest PackageParserTest

Change-Id: Ie238338a4cf1eb8ab10c9e22c9234a437b5fab7d