copyIndividualParts method
Copies all individually loaded parts from other
to this message.
Implementation
void copyIndividualParts(MimeMessage other) {
final otherIndividualParts = other._individualParts;
if (otherIndividualParts != null) {
for (final key in otherIndividualParts.keys) {
final value = otherIndividualParts[key];
if (value != null) {
setPart(key, value);
}
}
}
}