Merge "Add getSubscriptionId API" am: e9da3a19a1

Original change: https://android-review.googlesource.com/c/platform/packages/services/Telephony/+/2470130

Change-Id: Ifc2a0d5f63f87860335fa14ba077e6d70c40fc0a
Signed-off-by: Automerger Merge Worker <[email protected]>