message: Fix build on Mac OS.
diff: @@ -1328,8 +1328,7 @@ Status Host::ShellExpandArguments(ProcessLaunchInfo &launch_info) {
  if (!str_sp)
  continue;
  - launch_info.GetArguments().AppendArgument(
  - llvm::StringRef(str_sp->GetValue().c_str()));
  + launch_info.GetArguments().AppendArgument(str_sp->GetValue());
  }
  }
  