Without this commit, JVM name mapping logic in BE does not work for FIR, because FIR cannot use old BuiltInsPackageFragmentImpl descriptor. In this commit we add our own implementation thus fixing a pack of FIR black box tests.
These tests check behavior of an old language version on purpose: the original bug KT-24708 has been fixed by introducing an error here in 1.4.
#KT-24708 Fixed