Bind self to the class being defined when checking multiple inheritance

[sterliakov]

Fixes #18458.

When checking base class compatibility, the class being defined is not yet in scope. However, it should be equivalent to the class passed to bind_and_map_method with free typevars, as that's exactly what we are currently defining.

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

pandas (https://github.com/pandas-dev/pandas)
+ pandas/io/common.py:956: error: Unused "type: ignore" comment  [unused-ignore]
+ pandas/core/arrays/datetimes.py:174: error: Unused "type: ignore" comment  [unused-ignore]
+ pandas/core/arrays/_mixins.py:93: error: Unused "type: ignore" comment  [unused-ignore]
+ pandas/core/arrays/numpy_.py:48: error: Unused "type: ignore" comment  [unused-ignore]
+ pandas/core/arrays/datetimelike.py:199: error: Unused "type: ignore" comment  [unused-ignore]
+ pandas/core/arrays/categorical.py:247: error: Unused "type: ignore" comment  [unused-ignore]

ibis (https://github.com/ibis-project/ibis)
- ibis/expr/operations/core.py:21: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/core.py:43: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/relations.py:36: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:32: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:41: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:54: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:67: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:79: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:90: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:101: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:120: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:138: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:156: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:184: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:197: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:233: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:254: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:279: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:290: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:301: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:310: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:319: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:328: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:338: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:348: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:359: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:373: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:395: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/reductions.py:404: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/generic.py:180: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/vectorized.py:36: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/vectorized.py:44: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/operations/geospatial.py:186: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/expr/rewrites.py:29: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_graph_benchmarks.py:15: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_graph.py:204: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_graph.py:246: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:123: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:158: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:175: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:191: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:195: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]
- ibis/common/tests/test_egraph.py:211: error: Definition of "__recreate__" in base class "Annotable" is incompatible with definition in base class "Node"  [misc]

[sterliakov]

Hm, looks great - all removed errors are essentially equivalent to the snippet in #18458.

[ilevkivskyi]

Yes, I think this makes sense.