add export of TextCapitalization to text_field.dart (#19955)
add export of TextCapitalization to text_field.dart (#19955)


cbracken/flutter,tvolkert/flutter,tvolkert/flutter,cbracken/flutter,flutter/flutter,flutter/flutter,flutter/flutter,Hixie/flutter,flutter/flutter,flutter/flutter,cbracken/flutter,tvolkert/flutter,Hixie/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,tvolkert/flutter,Hixie/flutter,tvolkert/flutter,cbracken/flutter,tvolkert/flutter,cbracken/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,Hixie/flutter,Hixie/flutter,flutter/flutter,cbracken/flutter,flutter/flutter,flutter/flutter,cbracken/flutter,cbracken/flutter,Hixie/flutter,tvolkert/flutter,flutter/flutter,cbracken/flutter,tvolkert/flutter,tvolkert/flutter,tvolkert/flutter