[usecase-cordova][xwalk-2872] Fix the text overflow in Info button

- Add 'overflow-y' to show scroll when the text of Info popup is too long
- Fail reason: XWALK-2648

Impacted tests(approved): new 0, update 1, delete 0
Unit test platform: [Android]
Unit test result summary: pass 0, fail 1, block 0
Merge pull request #1133 from haoxli/usecase-cordova/xwalk-2872

[usecase-cordova][xwalk-2872] Fix the text overflow in Info button