swift234

Use the correct locator when converting an expression to its contextual type.

We were inferring the locator from an already-rewritten expression,
which resulted in a completely useless locator. Use the correct
(pre-rewrite) locator. Also, eliminate the Solution::coerceToType()
overload that infers the locator, since it was inferred the wrong
thing in two out of the three callers. Fixes <rdar://problem/14429520>.


Swift SVN r6448