[usecase-webapi] Fix style issue and add icon in Viewport

 Impacted TCs num: New 0, Update 4, Delete: 0
 Unit test platform: Android
 Unit test result: Pass 4, Fail 0, Block 0
Merge pull request #824 from Honry/Honry/usecase-fix-style-issue

[usecase-webapi] Fix style issue and add icon in Viewport