message: Fix macos build for r335244
  I've made the code accept only 16 byte UUIDs, which is technically not
  NFC (previously it would also accept 20 byte ones, but use only the
  first 16 bytes), but this should be more correct as mac UUIDs are always
  16 byte long.
diff: @@ -76,8 +76,8 @@ int LocateMacOSXFilesUsingDebugSymbols(const ModuleSpec &module_spec,
  if (uuid && uuid->IsValid()) {
  // Try and locate the dSYM file using DebugSymbols first
  - const UInt8 *module_uuid = (const UInt8 *)uuid->GetBytes();
  - if (module_uuid != NULL) {
  + llvm::ArrayRef<uint8_t> module_uuid = uuid->GetBytes();
  + if (module_uuid.size() == 16) {
  CFCReleaser<CFUUIDRef> module_uuid_ref(::CFUUIDCreateWithBytes(
  NULL, module_uuid[0], module_uuid[1], module_uuid[2], module_uuid[3],
  module_uuid[4], module_uuid[5], module_uuid[6], module_uuid[7],
  