[webapi-usecase] Intergation of all subcases to one page for CSSStyleAttribute

- Fail Reason:[XWALK-1326]

Impacted TCs num: New 0, Update 1, Delete 0
Unit test Platform: [Andriod]
Unit test result summary: Pass 0, Fail 1, Blocked 0
Merge pull request #714 from JianfengXu/xujf/style/update

[webapi-usecase] Intergation of all subcases to one page for CSSStyleAttribute