If some function is not fake-override, then its type should be just
default type of containing class
For fake overrides the default type calculated in the following way:
1. Find first overridden function, which is not fake override
2. Take its containing class
3. Find supertype of current containing class with type constructor of
class from step 2
^KT-60252 Fixed
As 'FirCodeFragments' are converted to IR independently of its context,
in some cases duplicate (and not quite correct) symbols for local
classes and functions are created.
Until properly fixed in fir2ir, here we replace such duplicates with
original symbols.
In the old JVM backend, local functions were compiled as JVM classes,
so there were an instance to pass around. Today, they are compiled to
static functions in the containing class/facade, and calls to them
compile natively.
Dmitriy Novozhilov