fix safeMode status in AppWidgetService

AppWidgetService uses safemode value that defined on SystemServiceManager.
however mSystemServiceManager.setSafeMode never called.
therefore AppWidgetService doesn't know whether safemode or not in boot phase.
In safemode, it causes NullPointerException in parsing function.
after that all of placed widgets disappear at launcher app.

Change-Id: I7576dcba7a2f548b2afa48ff2c700372c6920fe8