[webapi] update unitcommon.js for w3c nfc

- remove useless functions
- correct some type mistakes
- Failure analysis: nfc does not support

Impacted tests(approved): new 0, update 0, delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: pass 0, fail 12, block 0
Merge pull request #655 from zhangjingx/zjx/webapi/nfc_modify

[webapi] update unitcommon.js for w3c nfc