Description:
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DateTime class already has a getOffset to returns DST offset. But DateTimeZone has a parameter of DateTime, the result still returns only the DateTimeZone DST offset itself ? Should not it returns the offset between the DateTimeZone and the given parameter of DateTime ?

Reproduce code:
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$dateTimeZoneTaipei = new DateTimeZone("Asia/Taipei");
$dateTimeZoneJapan = new DateTimeZone("Asia/Tokyo");

$dateTimeTaipei = new DateTime("now", $dateTimeZoneTaipei);
$dateTimeJapan = new DateTime("now", $dateTimeZoneJapan);

$timeOffset = $dateTimeZoneJapan->getOffset($dateTimeTaipei);
var_dump($timeOffset);


Expected result:
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int(3600)

Actual result:
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int(32400)