make onActiveDataSubId in PhoneStateListener public API

Bug: 124260187
Test: CTS
Change-Id: I6e5a5c8273348d822b8f552599784b8e986850bf
Merged-In: I6e5a5c8273348d822b8f552599784b8e986850bf
(cherry picked from commit 026c42d7521c390b171f2b42a9b961fdc325b44a)
3 files changed