fix(heading-order): allow partial context to pass

[straker]

These changes allow partial heading-order context to pass. It will also handle iframes if they are included in the context or not.

Closes issue: #728

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[straker]

I have tried to debug this in IE11 for hours but can't figure out what's going on. It doesn't help that it's flakey for some reason. Best I can figure is that the iframe isn't running / returning axe results to the parent and so the iframe results are completely missing from the results object. Sometimes (rarely) the iframe times out and we get an error "Axe in frame timed out," but this doesn't happen every time the iframe results aren't in the results object.

A lot of the times when devtools are open the tests pass magically, or when I add console logs or debuggers. This makes me think it's a race condition, but I can't figure out where the problem is occurring in our integration runner.js script.

It also always passes if you just run the heading-order integration tests, so it has something to do with all the tests running before it...

Resolved

Resolved

[WilcoFiers]

Couple minor points

Resolved