The IsolatedConformances feature moves to a normal, supported feature.
Remove all of the experimental-feature flags on test cases and such.
The InferIsolatedConformances feature moves to an upcoming feature for
Swift 7. This should become an adoptable feature, adding "nonisolated"
where needed.
(cherry picked from commit 3380331e7e)
Instead of using the `isolated P` syntax, switch to specifying the
global actor type directly, e.g.,
class MyClass: @MainActor MyProto { ... }
No functionality change at this point
Extend the metadata representation of protocol conformance descriptors
to include information about the global actor to which the conformance is
isolated (when there is one), as well as the conformance of that type to
the GlobalActor protocol. Emit this metadata whenever a conformance is
isolated.
When performing a conforms-to-protocol check at runtime, check whether
the conformance that was found is isolated. If so, extract the serial
executor for the global actor and check whether we are running on that
executor. If not, the conformance fails.
