void markFailedConversion(@NotNull PsiType migrationType, PsiElement element) {
    final Pair<SmartPsiElementPointer<PsiElement>, PsiType> key =
      Pair.create(SmartPointerManager.getInstance(element.getProject()).createSmartPsiElementPointer(element), migrationType);
    if (!myFailedConversions.containsKey(key)) {
      myFailedConversions.put(key, getCurrentRoot());
    }
  }
void markFailedConversion(@NotNull PsiType migrationType, PsiElement element)