first round of Perl::Critic cleanups. Do not use return undef, use a bare return instead

lib/WebGUI/Workflow/Activity.pm

@@ -295,12 +295,12 @@ sub new {
 	my $session = shift;
 	my $activityId = shift;
 	my $main = $session->db->getRow("WorkflowActivity","activityId", $activityId);
-	return undef unless $main->{activityId};
+	return unless $main->{activityId};
 	$class = $main->{className};
     (my $module = "$class.pm") =~ s{'|::}{/}g;
     unless (eval { require $module; 1 }) {
         $session->errorHandler->error("Couldn't compile workflow activity package: ".$class.". Root cause: ".$@);
-        return undef;
+        return;
     }
 	my $sub = $session->db->buildHashRef("select name,value from WorkflowActivityData where activityId=?",[$activityId]);
 	my %data = (%{$main}, %{$sub});
@@ -334,14 +334,14 @@ sub newByPropertyHashRef {
         my $class = shift;
         my $session = shift;
         my $properties = shift;
-        return undef unless defined $properties;
-        return undef unless exists $properties->{className};
+        return unless defined $properties;
+        return unless exists $properties->{className};
         my $className = $properties->{className};
         my $cmd = "use ".$className;
         eval ($cmd);
         if ($@) {
                 $session->errorHandler->warn("Couldn't compile activity package: ".$className.". Root cause: ".$@);
-                return undef;
+                return;
         }
         bless {_session=>$session, _id=>$properties->{activityId}, _data => $properties}, $className;
 }

lib/WebGUI/Workflow/Cron.pm

@@ -176,7 +176,7 @@ sub new {
 	my $session = shift;
 	my $taskId = shift;
 	my $data = $session->db->getRow("WorkflowSchedule","taskId", $taskId);
-	return undef unless $data->{taskId};
+	return unless $data->{taskId};
 	bless {_session=>$session, _id=>$taskId, _data=>$data}, $class;
 }
 

lib/WebGUI/Workflow/Instance.pm

@@ -68,7 +68,7 @@ sub create {
         ? JSON::objToJson({parameters => $properties->{parameters}}, {pretty => 1, indent => 4, autoconv=>0, skipinvalid=>1}) 
         : undef;
 	my ($count) = $session->db->quickArray("select count(*) from WorkflowInstance where workflowId=? and parameters=?",[$properties->{workflowId},$params]);
-	return undef if ($isSingleton && $count);
+	return if ($isSingleton && $count);
 
     # create instance
 	my $instanceId = $session->db->setRow("WorkflowInstance","instanceId",{instanceId=>"new", runningSince=>time()});
@@ -203,7 +203,7 @@ Returns a reference to the next activity in this workflow from the current posit
 sub getNextActivity {
 	my $self = shift;
 	my $workflow = $self->getWorkflow;
-	return undef unless defined $workflow;
+	return unless defined $workflow;
 	return $workflow->getNextActivity($self->get("currentActivityId"));
 }
 
@@ -261,7 +261,7 @@ sub new {
 	my $session = shift;
 	my $instanceId = shift;
 	my $data = $session->db->getRow("WorkflowInstance","instanceId", $instanceId);
-	return undef unless $data->{instanceId};
+	return unless $data->{instanceId};
 	bless {_session=>$session, _id=>$instanceId, _data=>$data}, $class;
 }