message: [ObjectFileMachO] Catch up with FileDesc changes.
  This didn't show up because nobody built __arm64__ in a while.
  <rdar://problem/55916729>
diff: @@ -2680,8 +2680,8 @@ size_t ObjectFileMachO::ParseSymtab() {
  "dyld_shared_cache_", /* DYLD_SHARED_CACHE_BASE_NAME */
  header_arch.GetArchitectureName(), ".development");
  - FileSpec dsc_nondevelopment_filespec(dsc_path, false);
  - FileSpec dsc_development_filespec(dsc_path_development, false);
  + FileSpec dsc_nondevelopment_filespec(dsc_path);
  + FileSpec dsc_development_filespec(dsc_path_development);
  FileSpec dsc_filespec;
  UUID dsc_uuid;
  @@ -3127,7 +3127,7 @@ size_t ObjectFileMachO::ParseSymtab() {
  // second is the directory for the source
  // file so you end up with a path that looks
  // like "/tmp/src//tmp/src/"
  - FileSpec so_dir(so_path, false);
  + FileSpec so_dir(so_path);
  if (!FileSystem::Instance().Exists(so_dir)) {
  so_dir.SetFile(
  &full_so_path[double_slash_pos + 1],
  