[usecase-webapi]Update usecase for gamepad

- Use sample app from https://github.com/InternetExplorer/Gamepad-Sample to replace the existing usecase.
- Fail Reason: the gamepad can not connect to the android device, but this sample is passed in chrome 37.

Impacted TCs num: New 0, Update 1, Delete 0
Unit test Platform: Andriod
Unit test result summary: Pass 0, Fail 1, Blocked 0
Merge pull request #698 from JianfengXu/xujf/gamepad/usecase/update

[usecase-webapi]Update usecase for gamepad