Avoid calling getDownloadURL in favor of directly getting data

[stargazing-dino]

✨ What kind of change does this PR introduce? (Bug fix, feature, docs update...)

This would handle #240. I'm scared this adds an extra network call (possibly two but I don't think getReferenceFromUrl is a network req) so I won't I expect anything from this PR and the simplicity of getDownloadURL might be preferred.

I think the original bug is that the the extension is not being carried through to the path in either my implementation or the current one and that's what's causing this line to fail in the original issue:

final file = await FirebaseCacheManager().getSingleFile(audioURL);
// returns a file with a path of local_path/foo_bar instead of local_path/foo_bar.mp3

💥 Does this PR introduce a breaking change?

No

📝 Links to relevant issues/docs

firebase/firebase-js-sdk#76

🤔 Checklist before submitting

• All projects build
• Follows style guide lines (code style guide)
• Relevant documentation was updated
• Rebased onto current develop

[jdve]

Thanks for this PR! I hit an error due to CacheControl being null. I fixed it with this follow on change:

steppinglight@e0463d0

[stargazing-dino]

Thank you! I added your changes. I'll have to finish this on the weekend as another project is taking up my time

[stargazing-dino]

I just recently checked this again and it looks like it's working for me as expected. It might've been a cached older package I was using by accident. I'll move this out of draft and work on checklist. Pleas feel free to offer objections to my alternative

[stargazing-dino]

I'm afraid this is too stale. Closing for now to allow NNBD PR prior to any action here