swift234

Fix <rdar://problem/15858869> *all* objc accessors disabled in init methods, not just for self

This patch: 
 - Changes sema to set the "IsDirectPropertyAccess" on MemberRefExprs
   in inits/destructors that should be done directly because they are
   on the local object.
 - Removes the "SGF.AlwaysDirectStoredPropertyAccess" bool in SILGen,
   which was the source of the problem above and was otherwise problematic.

This will get a bit simpler when -enable-new-objc-properties rolls out. 


Swift SVN r12967