swift234

Sema: Force `dynamic` materializeForSet accessors to be statically dispatched.

The materializeForSet accessor for a `dynamic` property needs to dynamically invoke the getter and setter of the property in order to allow for runtime modification, so it doesn't need to be dynamically dispatched itself. If the property came from an imported ObjC class, then we can't dynamically dispatch it without polluting the selector namespace. Introduce a new 'ForcedStaticDispatch' bit and set it in order to force `dynamic` materializeForSet accessors to be statically dispatched. (They can't be `final` because it's legal to override a dynamic property.) If the property came from ObjC, register materializeForSet as an external declaration so it gets generated by SIL. Fixes rdar://problem/18706056.

Swift SVN r24930