Incorrect character count in TextField for extended grapheme clusters #54240
Description
The character count is wrong when a complex emoji such as 👨👩👦 is used in a TextField.
TextField(
maxLength: 10,
),
This is due to Flutter counting runes instead of graphemes. Read more about this problem in my solution proposal: https://docs.google.com/a/google.com/document/d/1OOFW0PEZf0orBl445YXJ3nfjyKOqZdmeQ6KU3glUh7s/edit?usp=sharing.