Before this commit we considered !isOverride as a sign that
function / field / accessor has no overridden symbols.
However, it's false for deserialized, because isOverride
is always false there.
This commit fixes 68 BB tests but breaks 25 BB tests (not yet muted)
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.
Library methods such as 'listOf' are resolved
to have the package fragments as their parents,
but JVM expects their containing file classes as parents.
This fix generates those file classes and
uses them as parent replacements for such library methods.
Most of these tests used this directive as a way to opt in to a new
language feature, and most of those features are already stable for a
long time, so no opt-in is needed. Some other tests used the directive
to opt out from a language feature, replace those by the `LANGUAGE`
directive. One test used the directive to test behavior that actually
depended on the API version; use `API_VERSION` directive there instead.
Mikhail Glukhikh