Strawman spec: https://mikewest.github.io/origin-policy/

WICG thread at https://discourse.wicg.io/t/proposal-set-origin-wide-policies-via-a-manifest/1617

public-webappsec@ thread at https://lists.w3.org/Archives/Public/public-webappsec/2016Jul/0046.html

Initial conversations seem pretty positive: perhaps this is something I can briefly introduce tomorrow, @torgo?