docs: function __detachChildren(node) {
              ASSERT(UTIL.isTrueObject(node.children));
              ASSERT(node.age >= CONSTANTS.MAX_AGE - 1);
  
              var children = node.children;
              node.children = null;
              node.age = CONSTANTS.MAX_AGE;
  
              for (var child in children) {
                  __detachChildren(children[child]);
              }
          }