Revert back to cmalloc

:Release Notes:
Use cmalloc instead of g_new0.

:Detailed Notes:
Looks like g_new0 doesn't have any advantages over cmalloc.
Reverting that change back.

:Testing Performed:
Unit tests succeeded under valgrind.

:QA Notes:

:Issues Addressed:
[GF-8743] Improve memory usage of jvalue

Open-webOS-DCO-1.0-Signed-off-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>

Change-Id: I859afaf99e14c8fe381f30ab021d144c874bd28d
Reviewed-on: https://g2g.palm.com/2972
Reviewed-by: Build Verification
Reviewed-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>
Tested-by: Anatolii Sakhnik <anatolii.sakhnik@lge.com>
Reviewed-by: Alekseyev Oleksandr <alekseyev.oleksandr@lge.com>
Tested-by: Alekseyev Oleksandr <alekseyev.oleksandr@lge.com>