swift234

When reporting a type error relating to the result type of an overload
set where all members of the set produce the same type, produce a more
specific error.

Before:

t.swift:4:17: error: no '&&' candidates produce the expected contextual result type 'Int'
  return a == b && 1 == 2
                ^
t.swift:4:17: note: produces result of type 'Bool'
  return a == b && 1 == 2
                ^

after:

t.swift:4:17: error: '&&' produces 'Bool', not the expected contextual result type 'Int'
  return a == b && 1 == 2
                ^

This improves the situation reported in https://twitter.com/_jlfischer/status/712337382175952896