There's two things that you may be referring to, so I'll answer both.
Logging out of the service:
If you call clearAllTokens() or clear cookies/localStorage some other way, it will not log the user out of the service (Facebook, Google, etc.). If the user goes to
facebook.com they will still be logged in.
Logging out of your app:
If you call clearAllTokens() that just means that further calls to get the token will not pull the token from the cache. Basically, it causes your app to "forget" about the user. You can implement your app in such a way that that means they're logged out, or you can automatically attempt to "remember" the user. Attempting to remember may cause a popup window to the auth provider to appear then quickly disappear.