Changed logic in screensaver jsondb backend
Changed logic in screensaver jsondb backend

Change-Id: I4fb96070102e44ec817b0d7d5d2609e20e14cd3d
Reviewed-by: Xizhi Zhu <6095b3dbb866d5a6b4a607e0cbd4aaa65e13c0b2@nokia.com>

qtproject/qtsystems,qtproject/qtsystems