Revisit MapboxMap plugin related extension functions to not use singletons

[kiryldz]

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Fixes: #73
<changelog>Revisit MapboxMap plugin related extension functions to not use singletons</changelog>

Pull request checklist:

• Briefly describe the changes in this PR.
• Include before/after visuals or gifs if this PR includes visual changes.
• Write tests for all new functionality. If tests were not written, please explain why.
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Summary of changes

Fix extension function usage in case of several instances of MapboxMap objects if using plugins.

User impact (optional)

[tobrun]

I appreciate the thinking outside the box. Moving the extension functions to SDK-base makes them always part of the SDK public API. We will conditionally execute APIs if the plugin dependency has been met. If we want to moe forward to such a setup, we can also replace the extension functions from sdk-base and add them directly on MapboxMap.

Note how this is conceptually different as the initial idea behind it. We only wanted to populate the MapboxMap API with new APIs if a plugin dependency was met. If you add animations plugin dependency, "magically" MapboxMap was able to use flyTo etc. without it, it wasn't.

[kiryldz]

I appreciate the thinking outside the box. Moving the extension functions to SDK-base makes them always part of the SDK public API. We will conditionally execute APIs if the plugin dependency has been met. If we want to moe forward to such a setup, we can also replace the extension functions from sdk-base and add them directly on MapboxMap.

Note how this is conceptually different as the initial idea behind it. We only wanted to populate the MapboxMap API with new APIs if a plugin dependency was met. If you add animations plugin dependency, "magically" MapboxMap was able to use flyTo etc. without it, it wasn't.

@tobrun - thanks a lot for such detailed write-up! I actually did not realize that bringing extension functions to sdk-base actually ruin all that "magic" as you described. I guess then indeed the best option is do it in a way @pengdev suggested.

[tobrun]

Super clean, I like it

[Chaoba]

LGTM

[pengdev]

Great work! can we add tests to these functions?

[kiryldz]

Great work! can we add tests to these functions?

Yep, working on that right now 👍