message: Remove unnecessary code.
  The implementation searches for absolute paths to .swiftmodule files
  in FileSpecs. This is not how we are supposed to find
  .swiftmodules. We are supposed to find them via N_AST symbols, or via
  dsymutil inside the ast section of the .dSYM.
  rdar://problem/39962565
diff: @@ -1242,18 +1242,6 @@ lldb::TypeSystemSP SwiftASTContext::CreateInstance(lldb::LanguageType language,
  }
  }
  }
  -
  - FileSpecList loaded_modules;
  -
  - sym_vendor->GetLoadedModules(lldb::eLanguageTypeSwift, loaded_modules);
  -
  - for (size_t mi = 0, me = loaded_modules.GetSize(); mi != me; ++mi) {
  - const FileSpec &loaded_module = loaded_modules.GetFileSpecAtIndex(mi);
  -
  - if (loaded_module.Exists())
  - swift_ast_sp->AddModuleSearchPath(
  - loaded_module.GetDirectory().GetCString());
  - }
  }
  if (!set_triple) {
  