Chrome 141 adds getDisplayMedia() windowAudio option

[chrisdavidmills]

Summary

Chrome/Edge desktop 141 add support for the getDisplayMedia() windowAudio option. See https://chromestatus.com/feature/5072779506089984.

This PR adds support for the new option. Note the slightly weird set of default values that differ across browsers and versions, and the partial implementation. I found these results by testing a modified version of https://mdn.github.io/dom-examples/screen-capture-api/basic-screen-capture/ with the new option added in.

Test results and supporting details

Related issues

[github-actions]

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[chrisdavidmills]

@eladalon1983, could you have a look at this compat data PR and let me know if it agrees with your understanding? The data is a bit weird, but this is what my tests showed.

[caugner]

Are we sure the default values are inversed between Chrome and Edge?

Your changes state:

• Chrome 141 = system, but Edge 141/142 = exclude
• Chrome 142+ = exclude, but Edge 143+ = system

[caugner]

Let's merge the partial statements:

Suggested change

	"chrome": [
	{
	"version_added": "142",
	"partial_implementation": true,
	"notes": [
	"Default value = `exclude`",
	"`window` value not supported"
	]
	},
	{
	"version_added": "141",
	"version_removed": "142",
	"partial_implementation": true,
	"notes": [
	"Default value = `system`",
	"`window` value not supported"
	]
	}
	],
	"chrome": {
	"version_added": "141",
	"partial_implementation": true,
	"notes": [
	"Defaults to `\"exclude\". Before Chrome 142, it defaulted to `\"system\"`.",
	"Only supports values `\"exclude\"` and `\"system\"`, not `\"window\"`."
	]
	},

[eladalon1983]

@eladalon1983, could you have a look at this compat data PR and let me know if it agrees with your understanding? The data is a bit weird, but this is what my tests showed.

I think @drkron should take it from here. :-)

[chrisdavidmills]

Are we sure the default values are inversed between Chrome and Edge?

Your changes state:

* Chrome 141 = `system`, but Edge 141/142 = `exclude`

* Chrome 142+ = `exclude`, but Edge 143+ = `system`

@caugner it sounds weird, but this is what I found during testing.

I agree with merging the partials; I've implemented the updates locally and then pushed.