Epiphany should manage HTTP auth passwords
The following discussion from !253 (merged) should be addressed:
OK wow, I didn't realize this API existed.
If you want to go deeper... we really need Epiphany to take over saving HTTP auth passwords, rather than WebKit. Seems like that's already possible using WebKitAuthenticationRequest and WebKitCredential, which I didn't realize. I thought we would need to add new API for this.
Basically: we should make WebKit never persist the credentials (
WEBKIT_CREDENTIAL_PERSISTENCE_FOR_SESSIONonly) and have Epiphany persist them instead, in the EphyPasswordManager with all your other Epiphany passwords. That way we stop saving HTTP auth passwords outside Epiphany-managed storage.