* only tap on widgets reachable by hit testing
* use FractionalOffset
* added tests
* check finder finds correct widget
* undo unintentional changes
* address comments
* style fix
* add Directionality in test
* fix analysis warning
Adds an initial integration test that:
1. captures laid-out widget size
2. focuses a text field to show the keyboard and resize the view
3. unfocuses the text field to dismiss the keyboard and resize the view
4. verify that the final widget size matches the initial size
