'Beta' tag for themed icon toggle am: dec7880032 am: 43cdc838e6 am: 026ebb8abd

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/apps/ThemePicker/+/15185264

Change-Id: I033e8d4cd29f72520246efcb4cec8f7525c91213