Point default referrer policy to a constant defined in RP spec

[krgovind]

This is a re-do of #952 started by @mikewest since I am taking over the relevant spec updates.

This spec will now point to a constant defined in w3c/webappsec-referrer-policy/pull/142 as the default referrer policy.

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Preview | Diff

[annevk]

Thank you! You'll need to make your membership of the googlers organization public.

[krgovind]

Thank you! You'll need to make your membership of the googlers organization public.

Done! It's my first time contributing to specs, so still discovering all the boxes I need to check off. :)

[annevk]

Great! (Landing this is blocked on w3c/webappsec-referrer-policy#142.)

[domfarolino]

LGTM! And as Anne said, I think we'll hold off on merging this until:

• Referrer Policy spec changes lands
• WPTs are ready to land

[krgovind]

Great! (Landing this is blocked on w3c/webappsec-referrer-policy#142.)

w3c/webappsec-referrer-policy#142 has now landed. Could we merge this please?

[annevk]

From the Referrer Policy issue:

• Chrome (WPTs)
• Firefox

Is there a Safari bug? At least I got the impression they did not ship a strict superset of this.

[krgovind]

Safari bug is here.

[annevk]

Thanks @krgovind! Glad this is mostly wrapped up now. I rebased the HTML PR and hopefully @domenic will have time for that soonish.