Revert "Update "Open networks available" toggle to instead open notification channel preferences."

This reverts commit 2c4b42c0b7.

Reason for revert: Need to use Settings.Global.WIFI_NETWORKS_AVAILABLE_NOTIFICATION_ON to toggle the feature because system NotificationChannels cannot be disabled.
Bug: 37794067
Test: m RunSettingsRoboTests

Change-Id: I6aaad78686f4fe929fd6bcd94897341fdaf6bd23

src/com/android/settings/utils/NotificationChannelHelper.java

@@ -1,64 +0,0 @@
-/*
- * Copyright (C) 2017 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.utils;
-
-import android.app.INotificationManager;
-import android.app.NotificationChannel;
-import android.os.RemoteException;
-
-/**
- * Wrappers around methods in {@link INotificationManager} and {@link NotificationChannel} to
- * facilitate unit testing.
- *
- * TODO: delete this class once robolectric supports Android O
- */
-public class NotificationChannelHelper {
-    private INotificationManager mNotificationManager;
-
-    public NotificationChannelHelper(
-            INotificationManager notificationManager) {
-        mNotificationManager = notificationManager;
-    }
-
-    /**
-     * Returns the notification channel settings for a app given its package name, user id, and
-     * channel id.
-     */
-    public NotificationChannelWrapper getNotificationChannelForPackage(String pkg, int uid,
-            String channelId, boolean includeDeleted) throws RemoteException {
-        NotificationChannel channel = mNotificationManager.getNotificationChannelForPackage(
-                pkg, uid, channelId, includeDeleted);
-        return channel == null ? null : new NotificationChannelWrapper(channel);
-    }
-
-    /**
-     * Wrapper around {@link NotificationChannel} to facilitate unit testing.
-     *
-     * TODO: delete this class once robolectric supports Android O
-     */
-    public class NotificationChannelWrapper {
-        private NotificationChannel mChannel;
-
-        public NotificationChannelWrapper(NotificationChannel channel) {
-            mChannel = channel;
-        }
-
-        public int getImportance() {
-            return mChannel.getImportance();
-        }
-    }
-}