Telephony: Return 'null' as per TelephonyManager need

Return 'null' instead of "" (empty string) when Line1AlphaTag,
IccSerialNumber and Msisdn are unavailable.

Bug: 8449375
Change-Id: I5d8052922363f4b3b900bcdea490afe22fedce4f
Telephony: Send complete path for EF-IMG(4F20) for RUIM cards.

When retrieving the EF_IMG from an RUIM the icon load fails
because the path to the EF is incorrectly specified as "img"

Bug: 8443193
Change-Id: I76f981d5334274b34e2e1a752fd0a550458e4e86
Merge "Telephony: Send complete path for EF-IMG(4F20) for RUIM cards."
Merge "Telephony: Return 'null' as per TelephonyManager need"
Merge branch 'master' into HEAD