[webapi][XWALK-3088] Update 2 cases for CSP

- Fail Reason: the frame-ancestors is not supported.

Impacted TCs num(approved): New 0, Update 2, Delete 0
Unit test Platform: [Tizen-IVI]
Unit test result summary: Pass 1, Fail 1, Blocked 0
Merge pull request #1562 from JianfengXu/csp/xwalk-3088

[webapi][XWALK-3088] Update 2 cases for CSP