Merge "Use isShownInPickerAt instead of isShownInPicker."

import java.io.PrintWriter;

import java.text.SimpleDateFormat;

import java.time.Instant;

import java.time.LocalTime;

import java.util.ArrayList;

import java.util.Calendar;

public class TimeUtils {

    /** @hide */ public TimeUtils() {}

    /** {@hide} */

    private static SimpleDateFormat sLoggingFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

    private static final SimpleDateFormat sLoggingFormat =

            new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

    /** @hide */

    public static final SimpleDateFormat sDumpDateFormat =

            new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");

    /**

     * This timestamp is used in TimeUtils methods and by the SettingsUI to filter time zones

     * to only "effective" ones in a country. It is compared against the notUsedAfter metadata that

     * Android records for some time zones.

     *

     * <p>What is notUsedAfter?</p>

     * Android chooses to avoid making users choose between functionally identical time zones at the

     * expense of not being able to represent local times in the past.

     *

     * notUsedAfter exists because some time zones can "merge" with other time zones after a given

     * point in time (i.e. they change to have identical transitions, offsets, display names, etc.).

     * From the notUsedAfter time, the zone will express the same local time as the one it merged

     * with.

     *

     * <p>Why hardcoded?</p>

     * Rather than using System.currentTimeMillis(), a timestamp known to be in the recent past is

     * used to ensure consistent behavior across devices and time, and avoid assumptions that the

     * system clock on a device is currently set correctly. The fixed value should be updated

     * occasionally, but it doesn't have to be very often as effective time zones for a country

     * don't change very often.

     *

     * @hide

     */

    public static final Instant MIN_USE_DATE_OF_TIMEZONE =

            Instant.ofEpochMilli(1546300800000L); // 1/1/2019 00:00 UTC

    /**

     * Tries to return a time zone that would have had the specified offset

     * and DST value at the specified moment in the specified country.

        List<String> timeZoneIds = new ArrayList<>();

        for (TimeZoneMapping timeZoneMapping : countryTimeZones.getTimeZoneMappings()) {

            if (timeZoneMapping.isShownInPicker()) {

            if (timeZoneMapping.isShownInPickerAt(MIN_USE_DATE_OF_TIMEZONE)) {

                timeZoneIds.add(timeZoneMapping.getTimeZoneId());

            }

        }