swift234

Several NFC changes:
 - In AST/Decl.cpp, simplify by always setting isMutating to true for 
   ctors/dtors, since mutability only means something to struct/enum 
   methods anyway.
 - in DeclContext.cpp, continue to lvalue qualify the 'self' of protocol 
   methods, this is currently dead.
 - in CSApply, fix logic for some value-type member processing stuff
   to properly handle methods that have a self which is not lvalue 
   qualified. Not exercised yet.


Swift SVN r11650