public static void clearContextInfo(PsiElement scope) {
    scope.putCopyableUserData(QUALIFIER_CLASS_KEY, null);
    scope.putCopyableUserData(REF_TO_CLASS, null);
    scope.putCopyableUserData(REF_TO_MEMBER, null);
    for (PsiElement child = scope.getFirstChild(); child != null; child = child.getNextSibling()) {
      clearContextInfo(child);
    }
  }
public static void clearContextInfo(PsiElement scope)