code: function removeFromSanctuary(parent) {
          var comments = queryComments(parent)
          for (var i = 0, comment; comment = comments[i++]; ) {
              if (comment.nodeValue == "ms-if") {
                  var msIfEl = comment.elem
                  if (msIfEl.parentNode) {
                      msIfEl.parentNode.removeChild(msIfEl)
                  }
              }
          }
          parent.textContent = ""
      }
docs: 将通过ms-if移出DOM树放进ifSanctuary的元素节点移出来，以便垃圾回收