Check for successful tar response in TarFetchedCallback

[danesfeder]

We can check for a successful Response in the TarFetchedCallback to provide more information for situations like #1618, where developers are using tokens are aren't compatible with offline routing.

The main point of this PR was:

  @Override
  public void onResponse(@NonNull Call<ResponseBody> call, @NonNull Response<ResponseBody> response) {
    if (response.isSuccessful()) {
      downloadTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, response.body());
    } else {
      OfflineError error = new OfflineError(response.message());
      downloader.onError(error);
    }
  }

But, I also took some time to extract some of the callbacks and listeners that were living in the RouteTileDownloader. By extracting them, we can add tests to verify the business logic being executed in each callback or listener. I did not change any business logic, this was mainly shuffling classes around / adding constructors for the dependencies they needed.

[codecov-io]

Codecov Report

Merging #1620 into master will increase coverage by 0.81%.
The diff coverage is 87.87%.

@@             Coverage Diff              @@
##             master    #1620      +/-   ##
============================================
+ Coverage     22.76%   23.58%   +0.81%     
- Complexity      704      728      +24     
============================================
  Files           189      193       +4     
  Lines          8244     8276      +32     
  Branches        609      609              
============================================
+ Hits           1877     1952      +75     
+ Misses         6184     6139      -45     
- Partials        183      185       +2

[Guardiola31337]

Great work @danesfeder

I've left a couple of minor comments / questions.

Thanks for running with this one.

[Guardiola31337]

Could you extract (if possible) some of the shared arrange code across these tests into a private factory method?

[Guardiola31337]

Could you extract (if possible) some of the shared arrange code across these tests into a private factory method?

[Guardiola31337]

It'd be 💯 appending the response code to the error message.

[Guardiola31337]

For extra context these are the messages used in iOS mapbox/mapbox-navigation-ios#1892

[akitchen]

Deep link -> here

[Guardiola31337]

How about extracting this magic number into a constant?

[danesfeder]

@Guardiola31337 thanks for the feedback, this is updated

[Guardiola31337]

Thanks for addressing the feedback @danesfeder

🚢:ship::ship: