async findQualifiedChildren(instance, depth) {
    var _a;

    if (this.componentFilter.isQualified(instance) && !((_a = instance.type.devtools) === null || _a === void 0 ? void 0 : _a.hide)) {
      return [await this.capture(instance, null, depth)];
    } else if (instance.subTree) {
      // TODO functional components
      const list = this.isKeepAlive(instance) ? this.getKeepAliveCachedInstances(instance) : this.getInternalInstanceChildrenByInstance(instance);
      return this.findQualifiedChildrenFromList(list, depth);
    } else {
      return [];
    }
  }
Find qualified children from a single instance.
If the instance itself is qualified, just return itself.
This is ok because [].concat works in both cases.

@param {Vue|Vnode} instance
@return {Vue|Array}