[usecase-webapi] Improve NBS usecase.

- Fix the bug that nothing happen after click "Request" button.
- Draw a message frame to show NBS messages above the buttons.

Impacted tests(approved): New 0, Update 1, Delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: Pass 1, Fail 0, Block 0
[usecase-wrt]update script click button event

Impacted TCs num(approved): New 0, update 2, deleted 0
Unit test platform: [tizen]
Unit test result summary: Pass 1, Fail 0, Blocked 1
Block reason: zoom pic no device to check.
[wrt] Update tcs and script for wrt-packertool-android-tests

Impacted tests(approved): new 88, update 174, delete 0
Unit test platform: [Android]
Unit test result summary: pass 262, fail 0, block 0
[misc] update/add tcs for  web-mbat-tests

[Detailed commit message (if have)]
Impacted TCs num(approved): New 1, update 8, deleted 7
Unit test platform: [tizen]
Unit test result summary: Pass 8 , Fail 1, Blocked 0
Crosswalk_WebApp_Update: wgt can not update
BUGID:https://crosswalk-project.org/jira/browse/XWALK-2296
[wrt][xwalk-2307/2294/2320] Add one TC for wrt-manifestspecificmanu-android-tests

Impacted TCs num(approved): New 1, Update 0, Delete 0
Unit test Platform: Android
Android test result summary: Pass 1, Fail 0, Block 0
Merge pull request #733 from linshen/wrt-usecase-tizen-alert

[usecase-wrt]update script click button event
[usecase-system][XWALK-1473] Add a TC for WebRTC

- Add a TC for WebRTC
- Failure analysis: The first channel onDataChannel can not be fired and the data channel name cannot be with space inside

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 #744 from linshen/wrt/update-mbat

[misc] update/add tcs for  web-mbat-tests
Merge pull request #740 from wanghongjuan/wanghongjuan/wrt/manifest-manu

[wrt][xwalk-2307/2294/2320] Add one TC for wrt-manifestspecificmanu-android-tests
[webapi][XWALK-2340] Change 39 TCs status to manual

- Change Reason: Need to confirm dialog during running these TCs in android.

Impacted TCs num(approved): New 0, Update 39, Delete 0
Unit test Platform: [Andriod]
Andriod test result summary: Pass 37, Fail 2, Blocked 0
[webapi][DeviceCapabilities] Use correct name of Event attribute.

Spec bugs: StorageUnit and DisplayUnit are type name.
The attribute name should be `storage` and `display`.
Add python.py to tools/build

Signed-off-by: Hao yunfeix <yunfeix.hao@intel.com>
Remove webkit prefix for page visibility

Impacted tests(approved): new 0, update 13, delete 0
Unit test platform: IVI
Unit test result summary: pass 13, fail 0, block 0
Merge pull request #749 from xiaojunwu/xioajunwu/pagevisibility-remove-prefix

Remove webkit prefix for page visibility
Merge pull request #748 from haoyunfeix/yunfei/add-pack-python-file

Add python.py to tools/build
Merge pull request #747 from legendlee1314/fixbug

[webapi][DeviceCapabilities] Use correct name of Event attribute.
Merge pull request #746 from JianfengXu/xujf/2340

[webapi][XWALK-2340] Change 39 TCs status to manual
Merge pull request #716 from kangxu/kangxu/wrt/wrt-packertool-android-tests/addTcs

[wrt] Update tcs and script for wrt-packertool-android-tests
Merge pull request #516 from minxhuang/hm/misc/usecase-tizen/NBS-hotfix

[usecase-webapi] Improve NBS usecase.
Merge pull request #730 from yunxliu/yunxliu/misc/webrtc_google

[usecase-system][XWALK-1473] Add a TC for WebRTC