[usecase][TC-1813] Add 1 usecase for Locale API

Impacted tests(approved) : new 1, update 0, delete 0
Unit test platform: [IVI]
Unit test result summary: pass 1, fail 0, block 0
Merge pull request #1358 from kangxu/kangxu/usecase/usecase-webapi-xwalk-tests/Locale

[usecase][TC-1813] Add 1 usecase for Locale API