Fixed failed with size of video

Before:
![editar video aula concursos voce wordpress](https://cloud.githubusercontent.com/assets/3674885/3938259/fbc9b428-24b7-11e4-95f5-c0176019ce36.png)
After:
![fixed_bug_video](https://cloud.githubusercontent.com/assets/3674885/3938264/0504b894-24b8-11e4-8c5a-7239e3ee6792.png)