Android : Intent manage. Old intent is resend if user open application from task-manager

I have a problem. When i call finish() method activity still hold in task-manager, and if user restart it from task-manager my activity receive old intent. If that intent was sent from push-notification I have unwanted reaction: my app start process intent with push-notification data.

How correctly manage push-notification intent behavior in my activity for avoid wrong activity state?

My app receive a push-notification and form pending intent for reaction on push:

       final NotificationManager mNotificationManager = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);

        int defaultOptions = Notification.DEFAULT_LIGHTS;
        defaultOptions |= Notification.DEFAULT_SOUND;

        Intent intentAction = new Intent(context, MainActivity.class);
        intentAction.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_SINGLE_TOP);
        intentAction.putExtra(BUNDLE_COLLAPSE_KEY, data.getString(BUNDLE_COLLAPSE_KEY));
        intentAction.setAction(CUSTOM_ACTION);

        final PendingIntent pendingIntent = PendingIntent.getActivity(context, 0, intentAction, PendingIntent.FLAG_UPDATE_CURRENT);
        int notificationFlags = Notification.FLAG_AUTO_CANCEL;
        final Notification notification = new NotificationCompat.Builder(context).setSmallIcon(R.drawable.icon_splash)
                .setContentTitle(context.getResources().getString(R.string.app_name))
                .setContentText(data.getString(BUNDLE_PUSH_CONTENT_DATA))
                .setContentIntent(pendingIntent)
                .setAutoCancel(true)
                .setDefaults(defaultOptions)
                .getNotification();
        notification.flags |= notificationFlags;
        mNotificationManager.notify(NOTIFICATION_ID, notification);

after user came in app from push, application, obviously, receive intent with CUSTOM_ACTION and do some work:

private void intentProcess(Intent intent) {
    boolean customAction = intent.getAction().equals(GCMPushReceiver.CUSTOM_ACTION);
    if (customAction) {
        //push reaction, do some staff with intent
    } else {
        //no push reaction, user just open activity
    }
}

I call intentProcess method from onCreate and from onNewIntent:

public class MainActivity extends FragmentActivity {
//this case if my app closed and user tap on push
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        /* ... */
        intentProcess(getIntent());
    }
//this case if my app opened and user tap on push
    @Override
    protected void onNewIntent(Intent intent) {
        super.onNewIntent(intent);
        intentProcess(intent);
    }
}

Activity declaration in manifest:

    <activity
        android:name=".ui.activity.MainActivity"
        android:label="@string/app_name"
        android:screenOrientation="portrait"
        android:windowSoftInputMode="adjustResize">
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>