This means that:
1. In test cases where minimal is the default (swift 5 without
-warn-concurrency), I added RUN lines for targeted, complete, and complete +
sns.
2. In test cases where complete is the default (swift 6, -warn-concurrency,
specified complete with -strict-concurrency), I added a send non-sendable run
line.
In each of these cases, I added additional expected-* lines as appropriate so
the tests can compile in each mode successfully.
The three options are now:
* `explicit`: Enforce Sendable constraints where it has been explicitly adopted and perform actor-isolation checking wherever code has adopted concurrency. (This is the default)
* `targeted`: Enforce Sendable constraints and perform actor-isolation checking wherever code has adopted concurrency, including code that has explicitly adopted Sendable.
* `complete`: Enforce Sendable constraints and actor-isolation checking throughout the entire module.
Determine whether a particular missing Sendable diagnostic should be
emitted as a warning or error, or even ignored entirely, based on the
emerging rules from the proposal for incremental adoption of Sendable
checking.
Extend the diagnostics for `Sendable` conformances to always diagnose
missing `Sendable` conformances for nominal types that are within the
same module. The intuition here is that if the type is in the same
module, it can be updated and evaluated at the same time as code
requiring the `Sendable` conformance is introduced.
Another part of rdar://78269348.