AndroidX support

[erickcchoi]

Fail to update the example project to Gradle 4.6 and Android Studio Gradle plugin 3.2.0.

[ryanheise]

Hi @erickcchoi

AndroidX support is definitely on the roadmap, and my plan is to finish implementing all open issues and then switch to AndroidX.

Reasoning: I can make a cutoff release where every release before it is pre-AndroidX and everything after it is AndroidX. But since there are still a lot of people who can't upgrade to AndroidX yet, I had better make the final pre-AndroidX release as good as it can be since it won't get any more updates after I move it to AndroidX.

Edit: When I say all open issues, I'll leave iOS off that list since I'm not personally working on that one.

[ryanheise]

I've just committed AndroidX support. Let me know if anything doesn't work and if there are no issues I'll publish a new release to pub.

[ryanheise]

Seems to be working so I'll close this issue.

[github-actions]

This issue has been automatically locked since there has not been any recent activity after it was closed. Please open a new issue for related bugs, or use StackOverflow if you need help with audio_service.