Update isNewEmoji to check Unicode 12.

Bug: 127811703
Test: Verified on Device.
Test: atest frameworks/base/core/tests/coretests/src/android/text/EmojiTest.java
Test: atest cts/tests/tests/text/src/android/text/cts/EmojiTest.java
Change-Id: Id2409dd96243bf74ff1c717a8cc458a6ebf24deb
2 files changed