@Nullable
    private static IdeaPlugin getSingleIncludingDescriptor(PsiElement element) {
      final VirtualFile[] includingFiles =
        FileIncludeManager.getManager(element.getProject()).getIncludingFiles(element.getContainingFile().getVirtualFile(), false);
      if (includingFiles.length != 1) return null;

      final PsiFile psiFile = element.getManager().findFile(includingFiles[0]);
      if (!(psiFile instanceof XmlFile)) return null;
      return DescriptorUtil.getIdeaPlugin(((XmlFile)psiFile));
    }
@Nullable
    private static IdeaPlugin getSingleIncludingDescriptor(PsiElement element)