This makes it possible to substitute 'flutter run' for 'flutter test'
and actually watch a test run on a device.
For any test that depends on flutter_test:
1. Remove any import of 'package:test/test.dart'.
2. Replace `testWidgets('...', (WidgetTester tester) {`
with `testWidgets('...', (WidgetTester tester) async {`
3. Add an "await" in front of calls to any of the following:
* tap()
* tapAt()
* fling()
* flingFrom()
* scroll()
* scrollAt()
* pump()
* pumpWidget()
4. Replace any calls to `tester.flushMicrotasks()` with calls to
`await tester.idle()`.
There's a guarding API that you can use, if you have particularly
complicated tests, to get better error messages. Search for
TestAsyncUtils.
As per the recent fix to the `always_specify_types` lint (https://github.com/dart-lang/linter/issues/199), literal maps and lists are now expected to be explicitly typed.
Running that lint on the repo identifies quite a few spots to update. This focuses on `flutter_driver` and `flutter_sprites` (somewhat arbitrarily) but the changes are fairly representative.
Note there are a number of places where I made a quick judgement on how specific to make the types. Feedback on those is welcome. (Especially as we move forward with more.)
