Add new @hide API to pass call direction changes through Telecom

Bug: 153277327
Fixes: 154245581
Test: atest TelecomUnitTests
Merged-In: Icad12c4144bf185c24ee80bcbdd1aec29550bf4e
Change-Id: Icad12c4144bf185c24ee80bcbdd1aec29550bf4e
6 files changed