Unregister all the receivers during test teardown.

import android.app.usage.NetworkStats;

import android.app.usage.NetworkStatsManager;

import android.app.usage.UsageStatsManagerInternal;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.content.IntentFilter;

import android.content.pm.ApplicationInfo;

import android.content.pm.IPackageManager;

import android.content.pm.PackageInfo;

import android.net.TelephonyNetworkSpecifier;

import android.net.wifi.WifiInfo;

import android.os.Binder;

import android.os.Build;

import android.os.Handler;

import android.os.INetworkManagementService;

import android.os.PersistableBundle;

import android.test.suitebuilder.annotation.MediumTest;

import android.text.TextUtils;

import android.util.ArrayMap;

import android.util.ArraySet;

import android.util.DataUnit;

import android.util.Log;

import android.util.Pair;

import com.android.server.pm.pkg.AndroidPackage;

import com.android.server.usage.AppStandbyInternal;

import libcore.io.Streams;

import com.google.common.util.concurrent.AbstractFuture;

import libcore.io.Streams;

import org.junit.After;

import org.junit.Assume;

import org.junit.Before;

import org.junit.Rule;

import org.junit.Test;

    private NetworkPolicyListenerAnswer mPolicyListener;

    private NetworkPolicyManagerService mService;

    private final ArraySet<BroadcastReceiver> mRegisteredReceivers = new ArraySet<>();

    /**

     * In some of the tests while initializing NetworkPolicyManagerService,

     * ACTION_RESTRICT_BACKGROUND_CHANGED is broadcasted. This is for capturing that broadcast.

            public void enforceCallingOrSelfPermission(String permission, String message) {

                // Assume that we're AID_SYSTEM

            }

            @Override

            public Intent registerReceiver(BroadcastReceiver receiver,

                    IntentFilter filter, String broadcastPermission, Handler scheduler) {

                mRegisteredReceivers.add(receiver);

                return super.registerReceiver(receiver, filter, broadcastPermission, scheduler);

            }

            @Override

            public Intent registerReceiverForAllUsers(BroadcastReceiver receiver,

                    IntentFilter filter, String broadcastPermission, Handler scheduler) {

                mRegisteredReceivers.add(receiver);

                return super.registerReceiverForAllUsers(receiver, filter, broadcastPermission,

                        scheduler);

            }

        };

        setNetpolicyXml(context);

        RecurrenceRule.sClock = Clock.systemDefaultZone();

    }

    @After

    public void unregisterReceivers() throws Exception {

        for (BroadcastReceiver receiver : mRegisteredReceivers) {

            mServiceContext.unregisterReceiver(receiver);

        }

    }

    @Test

    public void testTurnRestrictBackgroundOn() throws Exception {

        assertRestrictBackgroundOff();

    @Test

    public void testNormalizeTemplate_duplicatedMergedImsiList() {

        // This test leads to a Log.wtf, so skip it on eng builds. Otherwise, Log.wtf() would

        // result in this process getting killed.

        Assume.assumeFalse(Build.IS_ENG);

        final NetworkTemplate template = new NetworkTemplate.Builder(MATCH_CARRIER)

                .setSubscriberIds(Set.of(TEST_IMSI)).build();

        final String[] mergedImsiGroup = new String[] {TEST_IMSI, TEST_IMSI};