Add support to debug virtual authenticators

[nsatragno]

Description

This patch adds support for the addCredential, getCredentials, removeCredential, removeAllCredentials and setUserVerified commands of the WebAuthn automation API.

To add these methods directly into the VirtualAuthenticator class, I extracted it into an interface and implemented a RemoteVirtualAuthenticator as inner class of RemoteWebDriver.

Motivation and Context

Support more WebAuthn use cases:

• Trying an assertion without having to create a credential first.
• Handle user verification failures.
• Use specific private keys to back credentials.
• Handle credentials being cleared from an authenticator gracefully.

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

Fixes #7829

[shs96c]

This is great. Thank you! I love that it has tests too :) I'll wait for your comments before landing this. Feel free to disagree with anything: a lot of my comments are just questions.

[shs96c]

Nit: Map on the LHS.

It doesn't matter a huge amount, but I'm curious why you've used ImmutableMap elsewhere and not here.

[nsatragno]

I think an earlier version of my patch modified the map in place on RemoteWebDriver. Changed to ImmutableMap here and in VirtualAuthenticatorOptions for consistency. This means I had to add guava as a dependency to the bazel package -- ptal.

[shs96c]

Ah! We strive to make sure that the selenium-api doesn't need any third party libraries. If we want this to be immutable, the only Java 8 option is to use Collections.unmodifiableMap. The Map.of() method from Java 11 would be better, but we can't use that yet.

[nsatragno]

Removed the dependency and used Collections.unmodifiableMap instead. Please take a look.

[claassistantio]

All committers have signed the CLA.

[nsatragno]

Thank you for your quick review! Comments addressed below:

[nsatragno]

I think an earlier version of my patch modified the map in place on RemoteWebDriver. Changed to ImmutableMap here and in VirtualAuthenticatorOptions for consistency. This means I had to add guava as a dependency to the bazel package -- ptal.