Add SecureContext and API behavior of browsers

[marcoscaceres]

Closes #25

The following tasks have been completed:

• Modified Web platform tests

Implementation commitment:

• WebKit (https://bugs.webkit.org/show_bug.cgi?id=201221)
• Chromium - all tests pass
• Gecko - all tests pass

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Preview | Diff

[anssiko]

I think this PR would benefit from @foolip's review.

[marcoscaceres]

Probably want a nod from @annevk too :)

[annevk]

This doesn't end up invoking the failure callback.

[marcoscaceres]

Will add. Totally forgot to check that 🙃

[reillyeon]

For reference, in Blink the failure callback is called with a PositionError where code is PERMISSION_DENIED.

[marcoscaceres]

I’ll add some tests to see what we get across browsers.

[marcoscaceres]

Updated spec text and added tests web-platform-tests/wpt#18715

• Chrome and Firefox are aligned
• Safari returns error code 2 instead of 1.

cc @cdumez

[foolip]

idlharness.js tests will be updated by web-platform-tests/wpt#18717 after the spec change is merged.

[marcoscaceres]

Forgot to push before 🤪 should be good to review now.

[marcoscaceres]

Eventually, we need to go through and rewrite all these algorithms properly.

[cdumez]

@marcoscaceres Is WebKit returning POSITION_UNAVAILABLE instead of PERMISSION_DENIED the only thing failing in Safari? I am happy to fix this:
https://bugs.webkit.org/show_bug.cgi?id=201221

[marcoscaceres]

@cdumez, awesome! thanks for fixing it so quickly!

[marcoscaceres]

@reillyeon could you review the tests also? Then we should be good to land.

[marcoscaceres]

@anssiko could you please review the tests?

[anssiko]

@Honry PTAL

[marcoscaceres]

Ok, tests merged. Please merge this when possible. @anssiko, could you grant me write acceptance?

[anssiko]

Thanks @marcoscaceres for championing this fix and others for updating the implementations, we're ready to land now. @marcoscaceres you have been granted write.