Tailor grapheme boundaries so sequence emoji are one grapheme - DO NOT MERGE

Make it so it's not possible to position the cursor inside an emoji
formed by a sequence including zero-width joiners.

Bug: 25368653
Change-Id: I67ec0874cd1505f3c82ab91492ffc3d39a52fae6
1 file changed
tree: 6876504035e9ec5bd739e1ae9d6dada793626470
  1. app/
  2. doc/
  3. include/
  4. libs/
  5. sample/
  6. tools/