code: function (node) {
          function remove(dir) {
              var child;
              while ((child = node[dir]) && child.nodeType == 3 && domUtils.isWhitespace(child)) {
                  node.removeChild(child);
              }
          }
          remove('firstChild');
          remove('lastChild');
      }
docs: 删除node节点下首尾两端的空白文本子节点
  @method trimWhiteTextNode
  @param { Element } node 需要执行删除操作的元素对象
  @example
  ```javascript
  var node = document.createElement("div");
  
  node.appendChild( document.createTextNode( "" ) );
  
  node.appendChild( document.createElement("div") );
  
  node.appendChild( document.createTextNode( "" ) );
  
  //3
  console.log( node.childNodes.length );
  
  UE.dom.domUtils.trimWhiteTextNode( node );
  
  //1
  console.log( node.childNodes.length );
  ```