add tag for reauthenticateWithProvider snippet (#412)

Author: thatfiredev

auth/app/src/main/java/com/google/firebase/quickstart/auth/GenericIdpActivity.java

@@ -236,6 +236,7 @@ public void onFailure(@NonNull Exception e) {
     }
 
     public void reauthenticateWithProvider(OAuthProvider.Builder provider) {
+        // [START auth_oidc_provider_reauth]
         // The user is already signed-in.
         FirebaseUser firebaseUser = firebaseAuth.getCurrentUser();
 
@@ -258,5 +259,6 @@ public void onFailure(@NonNull Exception e) {
                                 // Handle failure.
                             }
                         });
+        // [END auth_oidc_provider_reauth]
     }
 }

auth/app/src/main/java/com/google/firebase/quickstart/auth/kotlin/GenericIdpActivity.kt

@@ -172,6 +172,7 @@ class GenericIdpActivity : AppCompatActivity() {
     }
 
     fun reauthenticateWithProvider(provider: OAuthProvider.Builder) {
+        // [START auth_oidc_provider_reauth]
         // The user is already signed-in.
         val firebaseUser = firebaseAuth.currentUser!!
         firebaseUser
@@ -185,5 +186,6 @@ class GenericIdpActivity : AppCompatActivity() {
             .addOnFailureListener {
                 // Handle failure.
             }
+        // [END auth_oidc_provider_reauth]
     }
 }