telephony: Privacy Guard support

 * Return empty lists for queries on SMS and MMS.

Change-Id: I2226a1d1529d6f0a005d8a27ddda91be8a654dcd

Conflicts:
	src/com/android/providers/telephony/MmsProvider.java
	src/com/android/providers/telephony/MmsSmsProvider.java
	src/com/android/providers/telephony/SmsProvider.java