编辑区文件title左侧，无文件标志，感觉V1好看点

![image](https://cloud.githubusercontent.com/assets/26532614/24092533/d2b83132-0d89-11e7-9780-8ffe1f936869.png)
![image](https://cloud.githubusercontent.com/assets/26532614/24092672/9b26e97e-0d8a-11e7-9ea2-b8cd6d64d1ee.png)




