[wrt][XWALK-1834] Add 2 new tcs for wrt-packagemgt-tizen-tests

Impacted Tc num(designed):New 2, UPdate 0, Delete 0
Unit test platform: Tizen
Unit test result summary:Pass 2, Fail 0,Block 0
Merge pull request #281 from linshen/add-xwalk-1834-tcs

[wrt][XWALK-1834] Add 2 new tcs for wrt-packagemgt-tizen-tests