swift234

Narrow trivial accessor creation to @objc VarDecls

Only create trivial accessors if the actual VarDecl is @objc,
explicitly or implicitly, not the class.

Also, replicate the PrintAsObjC test into classes_objc_generics since
"classes" isn't run on compilers that support Objective-C generics, and
fix the expectations.

Swift SVN r25162