Description:
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date_sunrise (date_sunset) incorrectly works with gmtoffset parameter. When i use SUNFUNCS_RET_TIMESTAMP, it ignores it and calculates date by adding UTC sunrise date and my location offset. When use SUNFUNCS_RET_STRING, all is ok. I don't checked SUNFUNCS_RET_DOUBLE.

Reproduce code:
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<?php
$lat = 43.1167; $lng = 131.9; //Vladivostok, Russia, UTC+10

date_default_timezone_set('Europe/Moscow'); //My location timezone, UTC+3

$zenith = 90+50/60;



$offset = 10; //Vladivostok

$sunrise_str = date_sunrise(time(),SUNFUNCS_RET_STRING,$lat,$lng,$zenith,$offset);
$sunrise_time = date_sunrise (time(),SUNFUNCS_RET_TIMESTAMP,$lat,$lng,$zenith,$offset);
echo "By string : $sunrise_str, by timestamp: ".date("Y-m-d H:i:s",$sunrise_time)."<br/>\n";



$offset = 0; //UTC

$sunrise_str = date_sunrise(time(),SUNFUNCS_RET_STRING,$lat,$lng,$zenith,$offset);
$sunrise_time = date_sunrise (time(),SUNFUNCS_RET_TIMESTAMP,$lat,$lng,$zenith,$offset);
echo "By string : $sunrise_str, by timestamp: ".date("Y-m-d H:i:s",$sunrise_time)."<br/>\n";



$offset = 3; //UTC plus my timezone offset

$sunrise_str = date_sunrise(time(),SUNFUNCS_RET_STRING,$lat,$lng,$zenith,$offset);
$sunrise_time = date_sunrise (time(),SUNFUNCS_RET_TIMESTAMP,$lat,$lng,$zenith,$offset);
echo "By string : $sunrise_str, by timestamp: ".date("Y-m-d H:i:s",$sunrise_time)."<br/>\n";
?>

Expected result:
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By string : 08:16, by timestamp: 2008-11-25 08:16:18
By string : 22:16, by timestamp: 2008-11-24 22:16:18
By string : 01:16, by timestamp: 2008-11-25 01:16:18

Actual result:
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By string : 08:16, by timestamp: 2008-11-25 01:16:18
By string : 22:16, by timestamp: 2008-11-25 01:16:18
By string : 01:16, by timestamp: 2008-11-25 01:16:18