Telephony: Add RIL request and event for OMH support

Change-Id: I8f68d6d9e1e188a2c2295a814376dccaaad5ec24

Conflicts:
	telephony/java/com/android/internal/telephony/DctConstants.java
	telephony/java/com/android/internal/telephony/RILConstants.java
telephony: add missing rilconstants.

Change-Id: I9ed8274b237254ac509a478b3200d075a3b2e6ad