go/types, types2: do not run CTI before FTI

Until now, CTI (constraint type inference) was run before
FTI (function type inference). This lead to situations
where CTI infered a type that is missing necessary methods
even though a function argument of correct type was given.
This can happen when constraint type inference produces a
inferred type that is the structural type of multiple types,
which then is an underlying type, possibly without methods.

This CL removes the initial CTI step; it is only applied
after FTI with type arguments is run, and again after FTI
with untyped arguments is run.

Various comments are adjusted to reflect the new reality.

Fixes #50426.

Change-Id: I700ae6e762d7aa00d742943a2880f1a1db33c2b8
Reviewed-on: https://go-review.googlesource.com/c/go/+/377594
Trust: Robert Griesemer <gri@golang.org>
Reviewed-by: Robert Findley <rfindley@google.com>

0 files changed, 0 insertions, 0 deletions