Move PackageParser2 to internal

1. PackageCacher is not used 9by client applications, so keep it on
the server side and replace it with a new interface. When the server
builds the parser, pass the correct object. The client just needs to
pass null.
2. Move out forParsingFileWithDefaults() from PackageParser2

Bug: 309596860
Test: build pass and boot to home
Test: atest PackageManagerServiceServerTests
Test: atest PackageManagerComponentOverrideTests
Test: atest PermissionServiceMockingTests
Test: atest PackageManagerServiceUnitTests
Test: atest PackageManagerPerfTests
Change-Id: I60818b829c82ae7bd6eb88030afce3a18704402c