Merge "[Mainline] Migrate TextUtils#emptyIfNull" am: 23438d66dd am: 562a34498f am: 8da61cc1f4

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1550514

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I14cc8f1f44b09c82ed9d897b904513d3ea49d558