Add tests for target-specific analysis options

[pq]

In https://dart-review.googlesource.com/c/sdk/+/334647, @scheglov suggests:

I would like to propose that we consider including tests that demonstrate our use of target-specific analysis options. These tests would help to ensure that we are using the most appropriate methods for each project and that we are getting the most accurate results possible. I believe that this would be a valuable addition to our testing suite and would help to improve the quality of our work.

I agree!