[usecase-webapi] Improve content usecase

- Scan complete to a pop up, not open in new page.
- Organize result to a table.
- Default show get Directory result.
- Update the button to "Open Dir".
- Fail Reason: DB connection error.

Impacted TCs num: New 0, Update 1, Delete 0
Unit test Platform: [Tizen-IVI]
Test result summary: Pass 0, Fail 1, Blocked 0
[behavior] Add subcase in tests xml

- Add subcase attribute in <testcase>
- Remove redundant element for behavior
[embedding][XWALK-1040] Add new embedding api tests for crosswalk

- use crosswalk-webview instead of xwalk_core_library in the README and pack.sh
- Add 24 cases about tests for embedding api. 10 of them are for XWalkExtension interface, others are for XWalkUIClient interface.
- Failure analysis:6 cases are failed because the methods of embedding api are not exist.

Impacted tests(approved): new 24, update 0, delete 0
Unit test platform: [Android]
Unit test result summary: pass 18, fail 6, block 0
Merge pull request #646 from JianfengXu/xujf/content/update

[usecase-webapi] Improve content usecase
Merge pull request #632 from haoxli/haoxli/behavior/subcase

[behavior] Add subcase in tests xml
Merge pull request #618 from zhuyongyong/yongzhu/embeddingAPI/add

[embedding][XWALK-1040] Add new embedding api tests for crosswalk
[wrt] Modify xpk to wgt and script
Merge pull request #672 from wanghongjuan/wanghongjuan/wrt/test

[wrt] Modify xpk to wgt and script