func foo() {}
let a: Int = #^HERE^#
Previously, we marked 'foo()' as 'NotRecommented' because 'Void' doesn't
have any member hence it cannot be 'Int'. But it wass confusing with
'deprecated'.
Now that we output 'typerelation' which is 'invalid' in this case. So clients
can deprioritize results, or even filter them out.
rdar://problem/57726512
We don't want to prioritize the type name for protocols, since they
can't be used (generally) to construct an instance of the type. Ideally
we would prioritize types that conform to the protocol.
For rdar://problem/24873625
When completing at the sequence position of for each statment (for i in <HRER> {}),
values of sequence type should have higher priority than the rest.
Swift SVN r32202
