Google's "secure browsers" policy refuses OAuth inside any WKWebView
regardless of UA, so signing into Spotify with a Google-linked account
in the in-app sheet dead-ended on Google's "browser may be insecure"
page. Intercept navigations to accounts.google.com / accounts.youtube.com
in both decidePolicyFor and the createWebViewWith popup path, redirect
back to Spotify's login screen, and surface a status message pointing
users at email/password/Apple/Facebook sign-in or the existing
"Open in Browser" escape hatch for Google accounts. Update the sheet's
initial banner so the limitation is visible before the user tries it.
Signed-off-by: Jis G Jacob <studiokeys@blissroms.org>
a92ee9c9b3