[wrt][xwalk-1548] Update 3 TCs steps due to the steps is incorrect

Impacted TCs num(approved): New 0, Update 3, Delete 0
Unit test Platform: IVI
Tizen test result summary: Pass 3, Fail 0, Block 0
Merge pull request #403 from wanghongjuan/wanghongjuan/wrt/xwalk-1548

[wrt][xwalk-1548] Update 3 TCs steps due to the steps is incorrect