Implement web platform tests for input validation steps

[huningxin]

The current WebNN web platform tests mainly focus on operator compute result (https://github.com/web-platform-tests/wpt/tree/master/webnn). There is a lack of test cases for input validation steps.

As @reillyeon mentioned in Chromium CL-5231640 for lstm,

it's important that we have a comprehensive test suite for the WebNN API which can be shared between backends in Chromium and with other browser vendors.

For these tests in particular, they are exercising input validation steps that are part of the specification and I feel that they are more appropriately expressed as web platform tests.

/cc @BruceDai

[huningxin]

@a-sully , I don't think this requires the spec change. I understand w-p-t is one deliverable of this WG. @anssiko , please correct me if I am wrong.

[anssiko]

That's correct. While test contributions go to the https://github.com/web-platform-tests/wpt repo we have used this WebNN spec repo to discuss non-trivial issues related to testing this API to guide test authors. These issues should be triaged with a testing label. The wpt repo is huge so any issues opened against it will get lost easily.

The relevant section in this WG's charter is Other Deliverables that says:

Test suite and implementation report for the specification;

[BruceDai]

I will take it and report status later.
@anssiko Please assign it to me, thanks

[BruceDai]

I'm working to add validation tests on web-platform-tests/wpt#44416.

[inexorabletash]

That PR landed - is there more work needed or can this be closed out?