Sync web-platform-tests PR 20375 into mozilla-central (this bug is closed when the sync is complete).

PR: https://github.com/web-platform-tests/wpt/pull/20375
Details from upstream follow.

Lan Wei <lanwei@chromium.org> wrote:

Allow another touch start happen when there are active touch points

Now when there are active touch points and we dispatch a touch start, an
error "Must have no prior active touch points to start a new touch." will
throw out. We should allow this case happens:
Input.dispatchEvent({
type: 'touchStart',
touchPoints: [{
x: 100,
y: 100,
id: 1
}]
});
Input.dispatchEvent({
type: 'touchStart',
touchPoints: [{
x: 100,
y: 100,
id: 1
}, {
x: 150,
y: 100,
id: 2
}]
});

Bug: 1020674
Change-Id: Ib5cae40864312977f03b2c9671edd7c46637be7c

Reviewed-on: https://chromium-review.googlesource.com/1927951
WPT-Export-Revision: bcc1b2790204be653dfe3db4a96fdc2cc1cc9d84

CI Results

Ran 13 Firefox configurations based on mozilla-central, and Firefox, Chrome, and Safari on GitHub CI

Total 1 tests and 1 subtests

Status Summary

Firefox

ERROR: 1

Chrome

OK : 1
PASS : 1

Safari

ERROR: 1

Links

Gecko CI (Treeherder)
GitHub PR Head
GitHub PR Base

Details

New Tests That Don't Pass

/infrastructure/testdriver/actions/multiTouchPointsTwoTouchStarts.html: ERROR (Chrome: OK, Safari: ERROR)

https://hg.mozilla.org/mozilla-central/rev/085f6082a047
https://hg.mozilla.org/mozilla-central/rev/7ac8e218433a