fix: added missing options to EmscriptenAudioWorkletNodeCreateOptions closes #23982

[nikitha-m]

Problem Description

The EmscriptenAudioWorkletNodeCreateOptions struct currently only exposes options specific to AudioWorkletNode itself (numberOfInputs, numberOfOutputs, outputChannelCounts), but AudioWorkletNode inherits from AudioNode which has additional properties:

• channelCount
• channelCountMode
• channelInterpretation

Fix

• Extend the C struct in system/include/emscripten/webaudio.h.
• Update the JavaScript implementation in src/lib/libwebaudio.js to pass these options to the AudioWorkletNode constructor.

Closes #23982

[juj]

channelCountMode and channelInterpretation are strings, so an integer will not work.

Create an enum for those, and in the JS code, index the enum into an array of strings.

See e.g. https://github.com/juj/wasm_webgpu/blob/3ed529956d1ee3f14f64c07769385e1929908f68/lib/lib_webgpu.js#L615 and https://github.com/juj/wasm_webgpu/blob/3ed529956d1ee3f14f64c07769385e1929908f68/lib/lib_webgpu.js#L729 in another repo for examples.

[juj]

This comment documents the history of evolution of the codebase (i.e. "before this PR, we had a 'basic' set, after this PR, we now have 'extended' set"), but in the Web Audio specification, there is no distinction between basic and extended options - there are just options.

So instead of documenting history of evolution, maybe add short comments that describe the new parameters?

[nikitha-m]

@juj how do i run test cases locally? I followed the docs but I'm facing some issues while running these commands

emsdk install tot
emsdk activate tot

[juj]

Yeah, that is how you install a pre-compiled Emscripten. If installing tot doesn't work, you can also try emsdk install latest followed by emsdk activate latest.

To run browser audio-related tests, you can run test/runner browser.test_*audio* and test/runner interactive.test_*audio*. The first suite is automated, but the second suite requires an interactive user to prod the tests forward.

If installing tot or latest doesn't work out, you can also try these steps to build all from source: https://bugzilla.mozilla.org/show_bug.cgi?id=1992558#c2