Interesting thing is Flutter was started as an experiment by guys on the chrome team, Ian Hickson, co-editor of the CSS 2.1 spec, works on Flutter as a TL. An aim of the Flutter team is to improve the developer experience.

Google uses a design pattern to helps to separate presentation from business logic, this allows them to share code across flutter and the web. https://pub.dartlang.org/packages/bloc

Here is the design bit from Flutter 1.0 live stream. https://youtu.be/NQ5HVyqg1Qc?t=5940