错误原因在于出现相同内容。
原写为：
<li ng-repeat="log in logs" scroll-down> {{log}}</li>
改写为：
<li ng-repeat="log in logs track by $index" scroll-down> {{log}}</li>
加track by $index即可解决。
[ngRepeat:dupes] Duplicates in a repeater are not allowed. Use 'track by' expression to specify unique keys
原文：http://www.cnblogs.com/hxb2015/p/4621490.html
