Validate ComponentName for MediaButtonBroadcastReceiver

     * Set the component name of the manifest-declared {@link android.content.BroadcastReceiver}

     * class that should receive media buttons. This allows restarting playback after the session

     * has been stopped. If your app is started in this way an {@link Intent#ACTION_MEDIA_BUTTON}

     * intent will be sent to the broadcast receiver.

     * <p>

     * Note: The given {@link android.content.BroadcastReceiver} should belong to the same package

     * as the context that was given when creating {@link MediaSession}.

     * intent will be sent to the broadcast receiver. On apps targeting Android U and above, this

     * will throw an {@link IllegalArgumentException} if the provided {@link ComponentName} does not

     * resolve to an existing {@link android.content.BroadcastReceiver broadcast receiver}.

     *

     * <p>Note: The given {@link android.content.BroadcastReceiver} should belong to the same

     * package as the context that was given when creating {@link MediaSession}.

     *

     * @param broadcastReceiver the component name of the BroadcastReceiver class

     * @throws IllegalArgumentException if {@code broadcastReceiver} does not exist on apps

     *     targeting Android U and above

     */

    public void setMediaButtonBroadcastReceiver(@Nullable ComponentName broadcastReceiver) {

        try {

package com.android.server.media;

import android.Manifest;

import android.annotation.NonNull;

import android.annotation.Nullable;

import android.annotation.RequiresPermission;

import android.app.ActivityManager;

import android.app.ActivityManagerInternal;

import android.app.PendingIntent;

import android.app.compat.CompatChanges;

import android.compat.annotation.ChangeId;

import android.compat.annotation.EnabledSince;

import android.content.ComponentName;

import android.content.Context;

import android.content.Intent;

import android.content.pm.PackageManager;

import android.content.pm.ParceledListSlice;

import android.content.pm.ResolveInfo;

import android.media.AudioAttributes;

import android.media.AudioManager;

import android.media.AudioSystem;

import android.media.session.PlaybackState;

import android.net.Uri;

import android.os.Binder;

import android.os.Build;

import android.os.Bundle;

import android.os.DeadObjectException;

import android.os.Handler;

import android.os.RemoteException;

import android.os.ResultReceiver;

import android.os.SystemClock;

import android.os.UserHandle;

import android.text.TextUtils;

import android.util.EventLog;

import android.util.Log;

 */

// TODO(jaewan): Do not call service method directly -- introduce listener instead.

public class MediaSessionRecord implements IBinder.DeathRecipient, MediaSessionRecordImpl {

    /**

     * {@link MediaSession#setMediaButtonBroadcastReceiver(ComponentName)} throws an {@link

     * IllegalArgumentException} if the provided {@link ComponentName} does not resolve to a valid

     * {@link android.content.BroadcastReceiver broadcast receiver} for apps targeting Android U and

     * above. For apps targeting Android T and below, the request will be ignored.

     */

    @ChangeId

    @EnabledSince(targetSdkVersion = Build.VERSION_CODES.UPSIDE_DOWN_CAKE)

    static final long THROW_FOR_INVALID_BROADCAST_RECEIVER = 270049379L;

    private static final String TAG = "MediaSessionRecord";

    private static final boolean DEBUG = Log.isLoggable(TAG, Log.DEBUG);

        }

    };

    @RequiresPermission(Manifest.permission.INTERACT_ACROSS_USERS)

    private static boolean componentNameExists(

            @NonNull ComponentName componentName, @NonNull Context context, int userId) {

        Intent mediaButtonIntent = new Intent(Intent.ACTION_MEDIA_BUTTON);

        mediaButtonIntent.addFlags(Intent.FLAG_RECEIVER_FOREGROUND);

        mediaButtonIntent.setComponent(componentName);

        UserHandle userHandle = UserHandle.of(userId);

        PackageManager pm = context.getPackageManager();

        List<ResolveInfo> resolveInfos =

                pm.queryBroadcastReceiversAsUser(

                        mediaButtonIntent, PackageManager.ResolveInfoFlags.of(0), userHandle);

        return !resolveInfos.isEmpty();

    }

    private final class SessionStub extends ISession.Stub {

        @Override

        public void destroySession() throws RemoteException {

        }

        @Override

        @RequiresPermission(Manifest.permission.INTERACT_ACROSS_USERS)

        public void setMediaButtonBroadcastReceiver(ComponentName receiver) throws RemoteException {

            final int uid = Binder.getCallingUid();

            final long token = Binder.clearCallingIdentity();

            try {

                //mPackageName has been verified in MediaSessionService.enforcePackageName().

                        != 0) {

                    return;

                }

                if (!componentNameExists(receiver, mContext, mUserId)) {

                    if (CompatChanges.isChangeEnabled(THROW_FOR_INVALID_BROADCAST_RECEIVER, uid)) {

                        throw new IllegalArgumentException("Invalid component name: " + receiver);

                    } else {

                        Log.w(

                                TAG,

                                "setMediaButtonBroadcastReceiver(): "

                                        + "Ignoring invalid component name="

                                        + receiver);

                    }

                    return;

                }

                mMediaButtonReceiverHolder = MediaButtonReceiverHolder.create(mUserId, receiver);

                mService.onMediaButtonReceiverChanged(MediaSessionRecord.this);

            } finally {