Fixes https://github.com/flutter/flutter/issues/89683.
The changes to `getFlutterView` in `FlutterDeviceScreenshot` are the fix that was required, everything else was done to get tests running (such as re-generating some lockfiles and modifying the android manifest).
The code was all currently not unit tested, and there were no other easy examples to base these java unit tests off in flutter/flutter, so let me know if this approach to testing is wrong.
* Revert "Mark last failing test after gradle update as flaky. (#91423)"
This reverts commit 46a52d03bd.
* Revert "fix android template for Gradle 7 (#91411)"
This reverts commit 51d06d537f.
* Revert "Add explicit version for mac and windows openjdk. (#91408)"
This reverts commit bf429f2771.
* Revert "Update the openjdk version used by linux android tests. (#91405)"
This reverts commit 2144ab8b45.
* Revert "Migrate to Gradle 7.0.2 / AGP 7.0.1 (#90642)"
This reverts commit b6459f9b63.
