add Bugzilla->urlbase method that returns a URI object

Bugzilla.pm

@@ -59,6 +59,7 @@ use Safe;
 use Sys::Syslog qw(:DEFAULT);
 use List::Util qw(any);
 use JSON::XS qw(decode_json);
+use URI;
 
 use parent qw(Bugzilla::CPAN);
 
@@ -272,6 +273,13 @@ sub localconfig {
     return $_[0]->process_cache->{localconfig} ||= 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 $_[0]->request_cache->{params} ||= Bugzilla::Config::read_param_file();
 }

Bugzilla/CGI.pm

@@ -664,7 +664,7 @@ 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.
     $paramhash{'-secure'} = 1

Bugzilla/Template.pm

@@ -925,7 +925,7 @@ sub create {
             'sudoer' => sub { return Bugzilla->sudoer; },
 
             # Allow templates to access the "corect" URLBase value
-            'urlbase' => sub { return Bugzilla->localconfig->{urlbase}; },
+            'urlbase' => sub { Bugzilla->urlbase },
 
             # Allow templates to access docs url with users' preferred language
             'docs_urlbase' => sub {