@Override
  public long getModificationStamp() {
    PsiElement context = getContext();
    PsiFile contextFile = context == null || !context.isValid() ? null : context.getContainingFile();
    long contextStamp = contextFile == null ? 0 : contextFile.getModificationStamp();
    return myModificationStamp + contextStamp;
  }
@Override
  public long getModificationStamp()