swift234

Emit diagnostics when multiple overload matches have the wrong function attribute

When threading a @noescape, @noreturn, or @autoclosure parameter through
to a function that doesn't expect one of those attributes, multiple
overload matches may cause the diagnostic to be dropped on the floor,
causing a crash in AST verification. If there is more than one failure
recorded for these attribute mismatches, don't fall back to the
contextual type diagnostics.

Fixes crash: rdar://problem/19704523

Swift SVN r24974