Clear up unused code

Test: make
Bug: 194833441
Change-Id: Icff8fe689626a6e92a119f9ed1a58656d15fbb47

tests/robotests/src/com/android/settings/testutils/shadow/ShadowNotificationBackend.java

@@ -1,37 +0,0 @@
-/*
- * Copyright (C) 2019 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *      http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License
- */
-
-package com.android.settings.testutils.shadow;
-
-import com.android.settings.notification.NotificationBackend;
-
-import org.robolectric.annotation.Implementation;
-import org.robolectric.annotation.Implements;
-
-@Implements(NotificationBackend.class)
-public class ShadowNotificationBackend {
-
-    private static int sBlockAppCount;
-
-    @Implementation
-    protected int getBlockedAppCount() {
-        return sBlockAppCount;
-    }
-
-    public static void setBlockedAppCount(int blockAppCount) {
-        sBlockAppCount = blockAppCount;
-    }
-}