OCSP and favicon isolation is only partly working in ESR 45

We might need a fixup patch for our OCSP and favicon isolation in ESR45. If one takes https://dist.torproject.org as an example URL I can see things like

[01-01 00:00:00] Torbutton INFO: tor SOCKS: https://dist.torproject.org/favicon.ico via torproject.org:0
[01-01 00:00:00] Torbutton INFO: tor SOCKS: https://dist.torproject.org/favicon.ico via --NoFirstPartyHost-chrome-browser.xul--:0

and

[01-01 00:00:00] Torbutton INFO: tor SOCKS: http://ocsp.digicert.com/ via torproject.org:0
[01-01 00:00:0=] Torbutton INFO: tor SOCKS: http://ocsp.digicert.com/ via --nofirstpartyhost-chrome-browser.xul--:0

in the log output. Note the differing nofirstpartyhost-chrome-browser.xul and Nofirstpartyhost-chrome-browser.xul.