@Override
      public void visitThisExpression(@NotNull PsiThisExpression expression) {
        super.visitThisExpression(expression);
        PsiElement parent = PsiUtil.skipParenthesizedExprUp(expression.getParent());
        if (!(parent instanceof PsiReferenceExpression)) {
          leak = true;
          stopWalking();
        }
      }
@Override
      public void visitThisExpression(@NotNull PsiThisExpression expression)