Fix to NullPointerException when activity is relaunched

When ChooseTypeAndAccountActivity is relaunched and resumed
by ActivityManager a call is made to onActivityResult without
first triggering onResume. This leads to mAccounts object
still being null.

Fixed by properly setting mAccounts object if it is null prior
to use after function onCreate has been called.

Change-Id: Ife7e1e052c473970d923fa43ee6189eb62a1113b
Avoid adding FORWARD_LOCK flag to an updated system app

Consider the following case:
1. An app exists in /system/app or /vendor/app. (i.e, it's a system app)
2. If the app would be updated as a forward-lock app by downloading from
   market(google play), then it would be installed in /data/app-private.
3. Moreover, if it would be updated by the whole system image (i.e, FOTA
   or something like that), then the app would be applied a FORWARD_LOCK
   flag.

The app SHOULD NOT have a FORWARD_LCOK flag. Because the resource path
of such app does not refer to the proper resources to access.

Change-Id: I0750f69a93a3115f4201029796b598507de3555f