add Bugzilla->urlbase method that returns a URI object

Bugzilla.pm

@@ -46,6 +46,7 @@ use File::Spec::Functions;
 use Safe;
 use JSON::XS qw(decode_json);
 use Scope::Guard;
+use URI;
 
 use parent qw(Bugzilla::CPAN);
 
@@ -162,6 +163,12 @@ sub localconfig {
     ||= Bugzilla::Localconfig->new(read_localconfig());
 }
 
+sub urlbase {
+  my ($class) = @_;
+
+  # Since this could be modified, we have to return a new one every time.
+  return URI->new($class->localconfig->{urlbase});
+}
 
 sub params {
   return request_cache->{params} ||= Bugzilla::Config::read_param_file();

Bugzilla/CGI.pm

@@ -520,7 +520,7 @@ sub send_cookie {
   }
 
   # Add the default path and the domain in.
-  state $uri = URI->new(Bugzilla->localconfig->urlbase);
+  state $uri = Bugzilla->urlbase;
   $paramhash{'-path'} = $uri->path;
 
   # we don't set the domain.

Bugzilla/Template.pm

@@ -985,7 +985,7 @@ sub create {
       'sudoer' => sub { return Bugzilla->sudoer; },
 
       # Allow templates to access the "correct" URLBase value
-      'urlbase' => sub { return Bugzilla->localconfig->urlbase; },
+      'urlbase' => sub { Bugzilla->urlbase },
 
       # Allow templates to get the absolute path of the URLBase value
       'basepath' => sub { return Bugzilla->localconfig->basepath; },