swift234

Break "NSUTF16" as "NSUTF, 16", not "NSUT, F16".

Previously, this declaration:

  typedef NS_OPTIONS(NSUInteger, NSABitmapFormat5) {
    NSAA16d,
    NSAB32d,
  };

...would import with members .A16d and .B32d, which is not necessarily
correct. (Is it "NS_AA_16d", or "NSA_A_16d"?) Be more conservative here.

Swift SVN r17125