Add unit test

Add unit test

[   75s]
============================================================================
[   75s] Testsuite summary for json-c 0.12
[   75s]
============================================================================
[   75s] # TOTAL: 12
[   75s] # PASS:  12
[   75s] # SKIP:  0
[   75s] # XFAIL: 0
[   75s] # FAIL:  0
[   75s] # XPASS: 0
[   75s] # ERROR: 0
[   75s]
============================================================================

[Model]
[BinType] AP
[Customer] OPEN

[Issue#] N/A
[Request] N/A
[Occurrence Version] N/A

[Problem]
[Cause & Measure]
[Checking Method] N/A

[Team] Open Source Management and Setting Part
[Developer] dh0128.kwak
[Solution company] Samsung
[Change Type] N/A

Change-Id: Ifd16cd617d92862c1787d618c651fd537805af1d
Signed-off-by: DongHun Kwak <dh0128.kwak@samsung.com>