Gate stricter manifest enforcement on targetSdk R

Two package parsing issues have been promoted to failures in R:
a missing <application>/<instrumentation> tag, and an empty
"android:name" attribute. The latter due to a bug in the parsing
code.

These need to be gated by targetSdkVersion so that APKs built for
previous versions can still scan/install properly. This change
introduces support for this through a framework that leverages
@ChangeId to introduce individually toggle-able errors, in
case a developer needs to install an app that isn't completely
migrated for a new SDK version yet.

The ignoreError method was removed from ParseResult as the errors
it was used for were manually compared to PackageParser and it's
likely they can be hard errors without breaking anything.

This also adds tests for general ParseInput/Result behavior.

Exempt-From-Owner-Approval: AppIntegrity already approved in older PS.

Bug: 150776642

Test: atest android.content.pm.parsing.result.ParseInputAndResultTest
Test: atest com.android.server.pm.parsing.PackageParsingDeferErrorTest
Test: atest com.android.server.integrity.AppIntegrityManagerServiceImplTest
Test: atest com.android.server.pm.parsing

Change-Id: Id53a2e65f6e5e4dee9a41cc77007275b3a220ac3