public static @Nullable VirtualFile descriptorFile(@NotNull VirtualFile root) {
    VirtualFile result = root.findChild(PsiJavaModule.MODULE_INFO_CLS_FILE);
    if (result == null) {
      result = ContainerUtil.getFirstItem(descriptorFiles(root, true, true));
    }
    return result;
  }
public static @Nullable VirtualFile descriptorFile(@NotNull VirtualFile root)