[webapi] Update xwalk_launcher to app_launcher

Impacted tests(approved): new 0, update 107, delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: pass 107, fail 0, block 0
Merge pull request #1109 from yunxliu/yunxliu/webapi/updateScript

[webapi] Update xwalk_launcher to app_launcher