Attach (recommended) or Link to PDF file here:
issue13500 (in test corpus)

This regressed when landing #13566. 

What is the expected behavior? (add screenshot)
<img width="664" alt="image" src="https://user-images.githubusercontent.com/942640/122467522-7bc8aa80-cf6f-11eb-9d4d-311eb7c64fb2.png">


What went wrong? (add screenshot)
![image](https://user-images.githubusercontent.com/942640/122467565-85eaa900-cf6f-11eb-9c10-8a8686ed440c.png)


return true;
  }
  [$setValue](value) {
    for (const field of this.field.children) {
      if (!field.value) {
        const nodeValue = new Value({});
        field[$appendChild](nodeValue);
        field.value = nodeValue;
      }
      const nodeBoolean = new BooleanElement({});
      nodeBoolean[$content] = 0;
      for (const item of field.items.children) {
        if (item[$hasItem](value)) {
          nodeBoolean[$content] = 1;
          break;
        }
      }
      field.value[$setValue](nodeBoolean);
    }
  }
  [$isSplittable]() {