Specify default passive for document-level wheel/mousewheel/touchstart/touchmove events

[zcorpan]

Fixes #365.

• At least two implementers are interested (and none opposed):
  • Already implemented in Gecko (except mousewheel event is not supported), Chromium, WebKit
• Tests are written and can be reviewed and commented upon at:
  • DOM: Test that some event listeners are passive by default web-platform-tests/wpt#34623
• Implementation bugs are filed:
  • Chrome: N/A
  • Firefox: https://bugzilla.mozilla.org/show_bug.cgi?id=1529953
  • Safari: N/A
  • Deno (only for aborting and events): …
  • Node.js (only for aborting and events): …

(See WHATWG Working Mode: Changes for more details.)

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[zcorpan]

This depends on whatwg/html#8017 (edit: is merged now)

[annevk]

Thank you for this PR! It's great to see this being tackled.

I found a couple nits and one more substantive issue.

[zcorpan]

@annevk thanks, fixed

[annevk]

I was going to merge this, but then I realized the tests might not be ready yet?

Suggested commit message:

Default passive for wheel/mousewheel/touchstart/touchmove events

In particular when the event listener is added on a Window object, Document object, document element, or the body element.

Tests: https://github.com/web-platform-tests/wpt/pull/34464.

Fixes #365.

[zcorpan]

Yeah, the tests still need review.

[zcorpan]

I've opened two wpt PRs:

• DOM: Test {mouse,}wheel and touch{move,start} events are non-cancelable when there are no non-passive event listeners web-platform-tests/wpt#34464 - this was first intended to test this spec change, but it was relying on a separate intervention. Now that PR only tests the separate intervention.
• DOM: Test that some event listeners are passive by default web-platform-tests/wpt#34623 - this now tests only this spec change.

[annevk]

Note that the reason I suggested the commit message above is because the one used isn't correct per https://github.com/whatwg/meta/blob/main/COMMITTING.md. Please keep that in mind for next time.

[zcorpan]

Oops, sorry about that.