[webapi] Update 3 TCs and add 28 TCs for MediaRenderer

- Update the playbackStatus attribute of type and add 28 basic TCs
- Failure analysis: The statuschanged event and rendererlost event cannot be fired

Impacted tests(approved): new 28, update 3, delete 0
Unit test platform: [Tizen IVI]
Unit test result summary: pass 52, fail 8, block 12
Merge pull request #789 from yunxliu/yunxliu/webapi/mediaRenderer_change

[webapi] Update 3 TCs and add 28 TCs for MediaRenderer