Incorrect inference of self in methods defined in superclasses in unbound methods on a subclass

[nelfin]

Steps to reproduce

import astroid
node = astroid.extract_node("""
class Base:
    def replace(self):
        return self

class Derived(Base):
    def method(self):
        return 123

this = Derived()
that = Derived.replace(this)
that
""")
inferred = next(node.infer())
inferred.getattr('method')

Current behavior

that is inferred as an instance of .Base not .Derived, causing this exception:

Traceback (most recent call last):
  File "astroid/bases.py", line 182, in getattr
    values = self._proxied.instance_attr(name, context)
  File "astroid/scoped_nodes.py", line 2433, in instance_attr
    raise exceptions.AttributeInferenceError(
astroid.exceptions.AttributeInferenceError: 'method' not found on <ClassDef.Base l.2 at 0x...>.

which leads to no-member warnings on pylint

Expected behavior

that is inferred as an instance of .Derived.

python -c "from astroid import __pkginfo__; print(__pkginfo__.version)" output

2.5.7

Related issues

Appears to be the root-cause of pylint-dev/pylint#4377.
Ref pylint-dev/pylint#4487