Add some examples of widgets that support visual density (#81932)
Add some examples of widgets that support visual density (#81932)


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