These are tests that fail in the next commit without this flag. This
does not add -verify-ignore-unrelated to all tests with -verify, only
the ones that would fail without it. This is NFC since this flag is
currently a no-op.
Compute a slice of ambiguous overload choices related to an aggregated fix
and if such a slice points to a single overload diagnose it as non-ambiguous.
Conformance requirements get their fixes attached directly where
other requirements have to use (for now) `repairFailure` mechanism.
Regardless of _how_ fixes get recorded there should be a single
way to assess impact of a particular requirement failure.
The rules are:
- If this is a requirement associated with an operator, impact
is based on use of the type which failed the requirement;
- If this requirement is from conditional extension,
it is considered a very high impact because failing such
requirement makes referenced member de facto invisible.
Resolves: rdar://problem/55593998
Resolves: [SR-11491](https://bugs.swift.org/browse/SR-11491)
Introduce a fix to detect and diagnose situations when omitted
generic arguments couldn't be deduced by the solver based on
the enclosing context.
Example:
```swift
struct S<T> {
}
_ = S() // There is not enough context to deduce `T`
```
Resolves: rdar://problem/51203824
