[webapi][XWALK-522] Optimize the test cases for promises

Impacted tests(approved): new 1, update 3, delete 0
Unit test platform: [Android]
Unit test result summary: pass 4, fail 0, block 0
[usecase-webapi] Disable forward button and show history state
[wrt] Update testapp for uxmanu and internetstdmanu
[usecase-webapi] Improve Systemsetting screen usecase.

- Add precondition before test to the info area after click the 'info' button.
- Remove section title for "Get HomeScreen/lockscreen image, canvasimage".
- Draw a frame to show HomeScreen image or LockScreen image.

Impacted tests(approved): New 0, Update 1, Delete 0
Unit test platform: [Tizen m0]
Unit test result summary: Pass 1, Fail 0, Block 0
[usecase-webapi] Improve Page Visibility usecase

- add description of locking screen/unlocking screen

Impacted TCs num(approved): New 0, Update 1, Delete 0
Unit test Platform: [Andriod]
Test result summary: Pass 1, Fail 0, Blocked 0
[usecase-webapi] Improve CSP usecase

- Add notice in csp-none page

Impacted TCs num(approved): New 0, Update 1, Delete 0
Unit test Platform: [Andriod]
Test result summary: Pass 1, Fail 0, Blocked 0
[usecase-webapi] Improve time usecase

- Change the date/time display to table.
- Put year/month/day in same line, h/m/s in another line.

Impacted TCs num(approved): New 0, Update 1, Delete 0
Unit test Platform: [Tizen-IVI]
Test result summary: Pass 1, Fail 0, Blocked 0
[usecase-webapi] Improve SVGTransformation usecase.

- Add description fot the animation.
- Add start position and end position on the screen.
- Improve pass cretia in info.

Impacted tests(approved): New 0, Update 1, Delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: Pass 1, Fail 0, Block 0
Merge pull request #585 from minxhuang/hm/misc/usecase-w3c/SVGTransfomation-hotfix

[usecase-webapi] Improve SVGTransformation usecase.
[misc] Improve cordove usecase
Merge pull request #621 from JianfengXu/xujf/time/update

[usecase-webapi] Improve time usecase
 [usecase-webapi] Improve Sandbox usecase.

- Remove "Tizen" and "Android" in test purpose.
- Change "Submit Form" to "Submit" in button.

Impacted tests(approved): New 0, Update 1, Delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: Pass 1, Fail 0, Block 0
Merge pull request #547 from minxhuang/hm/misc/usecase-w3c/Sanbox-hotfix

[usecase-webapi] Improve Sandbox usecase.
Merge pull request #615 from kangxu/kangxu/wrt/wrt-internetstdmanu-android-tests/update

[wrt] Update testapp for uxmanu and internetstdmanu
Merge pull request #521 from minxhuang/hm/misc/usecase-tizen/Systemsettingscreen-hotfix

[usecase-webapi] Improve Systemsetting screen usecase.
Merge pull request #620 from wanghongjuan/wanghongjuan/misc/update-usecase

[misc] Improve cordove usecase
Merge pull request #581 from JianfengXu/xujf/csp/update

[usecase-webapi] Improve CSP usecase
Merge pull request #551 from zhuyongyong/yongzhu/sessionHistory/begining

[usecase-webapi] Disable forward button and show history state
Merge pull request #530 from zhuyongyong/yongzhu/promise-optimize

[webapi][XWALK-522] Optimize the test cases for promises
Merge pull request #580 from zhangjingx/zhangjingx/misc/pagevisibility

[usecase-webapi] Improve Page Visibility usecase