test(functions): fix instrumentation tests

Author: thatfiredev

firebase-functions/src/androidTest/java/com/google/firebase/functions/TestFirebaseInstanceIdInternal.java

@@ -14,9 +14,15 @@
 
 package com.google.firebase.functions;
 
+import androidx.annotation.NonNull;
 import androidx.annotation.Nullable;
+
+import com.google.android.gms.tasks.Task;
+import com.google.android.gms.tasks.Tasks;
 import com.google.firebase.iid.internal.FirebaseInstanceIdInternal;
 
+import java.io.IOException;
+
 public class TestFirebaseInstanceIdInternal implements FirebaseInstanceIdInternal {
   private final String testToken;
 
@@ -34,4 +40,20 @@ public String getId() {
   public String getToken() {
     return testToken;
   }
+
+  @NonNull
+  @Override
+  public Task<String> getTokenTask() {
+    return Tasks.forResult(testToken);
+  }
+
+  @Override
+  public void deleteToken(@NonNull String s, @NonNull String s1) throws IOException {
+    // No-op: We're not using this method in our tests
+  }
+
+  @Override
+  public void addNewTokenListener(NewTokenListener newTokenListener) {
+    // No-op: We're not using this method in our tests
+  }
 }