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.
- Added tests to demonstrate broken behaviour: the interaction of inline
functions and callable references with varargs and defaults in various
combinations.
- Refactored InlineCallableReferencesToLambdaPhase to look like and use
some of the infrastructure from CallableReferenceLowering.
- Lifted some of this infrastructure out to be broadly reusable.