Code review comment for lp:~mardy/webbrowser-app/per-account-dir2

In this last change, is the "webContextSessionCookieMode" property on webappViewLoader effectively going to override the engine’s root context "webContextSessionCookieMode" property so that UbuntuWebContext pick it up correctly?

If so, the change looks ok to me, but a comment to explain that would be welcome, as it might seem like black magic to an external developer trying to understand the code.