Merge "Expose Telecom constants for use in Telephony" am: 9fcb2819d0 am: 1bf919f084 am: 5b6beb2fc0

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1427473

Change-Id: Icd1e3d555c35652720cb724caf0311ebfab9df34