This also requires some work in signon-ui and ubuntu-system-settings-online-accounts: Google doesn't allow the callback URL to end with a "/", but then when our webview is redirected to it, a "/" is appended to the address and signon-ui and ussoa don't recognize it.
This also requires some work in signon-ui and ubuntu- system- settings- online- accounts: Google doesn't allow the callback URL to end with a "/", but then when our webview is redirected to it, a "/" is appended to the address and signon-ui and ussoa don't recognize it.