Query PlatformCompat for targetSdk check in AndroidPackageParsingTestBase

There are prebuilts in the tree and perhaps APKs in general
which don't conform to the manifest checks added in R, so the code
that parses the APK to verify v1 vs v2 needs to actually query
PlatformCompat to do the proper targetSdkVersion check and allow
the APK through if it's not updated yet.

A related change to default enabled inside ParsingPackageImpl to
true was also made, as if any malformed APK was allowed through
without an <application> tag, it would never hit the code
where enabled gets assigned to default true.

Any further errors spit out by this test are critical and need to
updated so that their APKs can be installed on R.

Bug: 153058196

Test: manual verify error behavior with broken APK
Test: atest com.android.server.pm.parsing

Change-Id: I2b117f2098d8bd62b92921178a098e838b55b06d