Removes remaining one-tap sign-up documentation from README.

Author: bojeil-google

README.md

@@ -468,62 +468,6 @@ non HTTP/HTTPS environments.
 
 > **Note:** The beta test program for this API is currently closed.
 
-One-tap sign-up provides seamless authentication flows to
-your users with Google's one tap sign-up and automatic sign-in APIs.
-With one tap sign-up, users are prompted to create an account with a dialog
-that's inline with FirebaseUI NASCAR screen. With just one tap, they get a
-secure, token-based, passwordless account with your service, protected by their
-Google Account. As the process is frictionless, users are much more likely to
-register.
-Returning users are signed in automatically, even when they switch devices or
-platforms, or after their session expires.
-One-tap sign-up integrates with FirebaseUI and if you request Google OAuth
-scopes, you will still get back the expected Google OAuth access token even if
-the user goes through the one-tap flow. However, in that case 'redirect' flow is
-always used even when 'popup' is specified.
-In addition, if you choose to force prompt for Google sign-in, one-tap auto
-sign-in will be automatically disabled.
-One-tap is an additive feature and is only supported in the latest evergreen
-modern browser environments.
-
-The following example shows how to configure one-tap sign-up with FirebaseUI.
-Along with the corresponding one-tap `credentialHelper`, `clientId` and
-`authMethod` have to be provided with the Firebase Google provider:
-
-```javascript
-ui.start('#firebaseui-auth-container', {
-  signInOptions: [
-    {
-      // Google provider must be enabled in Firebase Console to support one-tap
-      // sign-up.
-      provider: firebase.auth.GoogleAuthProvider.PROVIDER_ID,
-      // Required to enable this provider in one-tap sign-up.
-      authMethod: 'https://accounts.google.com',
-      // Required to enable ID token credentials for this provider.
-      // This can be obtained from the Credentials page of the Google APIs
-      // console.
-      clientId: 'xxxxxxxxxxxxxxxxx.apps.googleusercontent.com'
-    },
-    firebase.auth.FacebookAuthProvider.PROVIDER_ID,
-    firebase.auth.TwitterAuthProvider.PROVIDER_ID,
-    firebase.auth.GithubAuthProvider.PROVIDER_ID,
-    firebase.auth.EmailAuthProvider.PROVIDER_ID,
-  ],
-  // Required to enable one-tap sign-up credential helper.
-  credentialHelper: firebaseui.auth.CredentialHelper.GOOGLE_YOLO
-});
-// Auto sign-in for returning users is enabled by default except when prompt is
-// not 'none' in the Google provider custom parameters. To manually disable:
-ui.disableAutoSignIn();
-```
-
-Auto sign-in for returning users can be disabled by calling
-`ui.disableAutoSignIn()`. This may be needed if the FirebaseUI sign-in page is
-being rendered after the user signs out.
-
-To see FirebaseUI in action with one-tap sign-up, check out the FirebaseUI
-[demo app](https://fir-ui-demo-84a6c.firebaseapp.com/).
-
 |Credential Helper |Value                                                 |
 |------------------|------------------------------------------------------|
 |accountchooser.com|`firebaseui.auth.CredentialHelper.ACCOUNT_CHOOSER_COM`|