Web updates

Web App Manifests 595ed56ee5ae

scope algorithm: Delete same-origin-as-document check. (#696) This was redundant, because a) the start_url is already checked to be same-origin-as-document, and b) the start_url is checked to be within scope of scope (which implies they are same-origin). Thus the scope is guaranteed to be same-origin as the document without this explicit check. This removes the document URL parameter to the scope algorithm. No normative changes. Work towards fixing #668.

Matt Giuca