Create dart:audio library that can be used in a browser or standalone VM

[justinfagnani]

The Web Audio API could be very useful outside of a browser, and very little of it is tied to browser environments and HTML that I can see.

This is different than issue #3108 which requests slitting the audio APIs from dart:html. I'd like to go one step further and make the API environment independent.

[sethladd]

What are some use cases for a standalone Audio API?

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Removed Type-Defect label.
Added Type-Enhancement, Area-Library, Triaged labels.

[dgrove]

We're all in on using the browser for rendering (both video and audio).

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Added Library-Html, WontFix labels.