ExtensionSet::GetHostedAppByURL calls URLPatternSet::MatchesURL, which calls URLPattern::MatchesURL.  That has hard-coded support for filesystem URLs (with a nested URL check from r135049), but it doesn't check for blob URLs.

url::Origin::Create has built-in support for obtaining the origin from a URL that might be a filesystem or blob URL, so it might be worth updating MatchesURL to use that or support blob URLs another way.

(One subtlety is that hosted apps may be restricted to a path on an origin in some cases, and that path is generally lost in filesystem and blob URLs.  It should be fine to address it the same way for both filesystem and blob, though, and this isn't a problem for hosted apps that apply to an entire origin.)

This is a followup to  issue 851503 .