Autogenerate NetworkStack jarjar rules

Use the jarjar rule generator for NetworkStack jarjar rules, to jarjar
classes to the com.android.networkstack package.  This also includes:

  - Moving some classes that cause less confusion if not jarjared to
    com.android.networkstack directly in source: exported services in
    the manifest (RegularMaintenanceJobService and ipmemorystore in
    general), classes with JNI registration (NetworkStackUtils).
  - Changing package-private visibility to public for some
    @VisibleForTesting members, because they are now in a package that
    does not match the test (for example ApfFilter, ApfGenerator usage
    in ApfTest). The jarjar rules currently jarjar tests if they match
    the name of a base class (so ApfFilter and ApfFilterTest would both
    be jarjared and share package-private visibility), but ApfTest
    cannot see package-private members in ApfFilter for example, since
    after this change only ApfFilter will be jarjared to a different
    package. An alternative would be to have separate jarjar rules for
    tests, but this would require heavy setup.
  - Updating the proguard flags for the new naming

Test: atest NetworkStackTests

Change-Id: I036665a6a63dfe0e7e090d8a7348bb4b95481f9d
37 files changed