Perl code for writing containers doesn't count length of write*Begin or write*End

The Perl code generator creates code for containers which doesn't count the length of their begin and end data, with the result that calling write on anything involving a map returns a length that's 6 bytes shorter than the actual amount written. The fix seems pretty obvious, adding $xfer += to the relevant lines in t_perl_generator::generate_serialize_container(). Here's an example of current generated code for example - note the lack of $xfer += before $output->writeMapBegin or ...End:

if (defined $self->

{fname}

) {
$xfer += $output->writeFieldBegin('fname', TType::MAP, 3);
{
$output->writeMapBegin(TType::STRING, TType::STRING, scalar(keys %{$self->{fname}}));
{
while( my ($kiter7,$viter8) = each %{$self->{fname}})

{ $xfer += $output->writeString($kiter7); $xfer += $output->writeString($viter8); }

}
$output->writeMapEnd();
}
$xfer += $output->writeFieldEnd();
}