Merge "Replace LanguageTag.isLanguage with public API" am: 1db88034cc am: 9cf8dd91bd

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1531679

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I6372256ffb1f56b7b55d09f3b9baec06b70db101