* Revert "Revert "Add RichText support to find.text" (#22046)"

This reverts commit 8e704219.

* Revert "Implement Double Tap Handling in TextField and Editable (#21264)"

This reverts commit 02e87334.

Thanks @NikoYuwono for getting this working! We appreciate your help!

* Implement Double Tap Handling in TextField and Editable

* Fix test broken by the change and add test for double tap

* Fix affected tests

* Remove unnecessary new

* Fix test

* enable lint unnecessary_new

* fix tests

* fix tests

* fix tests

Also:
 * Export TextInputAction from `text_field.dart` to parallel `TextInputType`.

Fixes #18145.