swift234

[linker] Link in closures references via function_refs during mandatory inlining.

Pattern matching on whether or not the function was applied is fragile
in the face of various possible compositions in between the function_ref
and the apply (i.e. thin_to_thick_function as an example).

Lets be conservative and just always deserialize references to closures
during mandatory inlining when referenced via a function_ref so we avoid
this problem if additional instructions like this are added.

Swift SVN r17977