mech's $res->base does not see <base href="">

mech-res-base.pl

use strict;
use warnings;
use Test::More;
use LWP::UserAgent;
use WWW::Mechanize;

my $ua = LWP::UserAgent->new;
my $mech = WWW::Mechanize->new;

subtest ua => sub {
    my $res = $ua->get('http://www.nicovideo.jp/tag/VOCALOID');
    is $res->base, 'http://www.nicovideo.jp/';
};

subtest mech => sub {
    my $res = $mech->get('http://www.nicovideo.jp/tag/VOCALOID');
    is $res->base, 'http://www.nicovideo.jp/'; # fail
};

done_testing;

__END__

    ok 1
    1..1
ok 1 - ua
    not ok 1
    #   Failed test at /Users/motemen/sketch.pl line 17.
    #          got: 'http://www.nicovideo.jp/tag/VOCALOID'
    #     expected: 'http://www.nicovideo.jp/'
    1..1
    # Looks like you failed 1 test of 1.
not ok 2 - mech
#   Failed test 'mech'
#   at /Users/motemen/sketch.pl line 18.
1..2
# Looks like you failed 1 test of 2.