fix errors generated when viewing last thread in cs

docs/changelog/7.x.x.txt

@@ -37,6 +37,7 @@
  - fix: Fixed SyncProfileToLDAP workflow activity to allow anonymous snycs
  - fix: Fixed SyncProfileToLDAP workflow activity to properly sync if RDN does not match DN
  - fix: SQL Report download link doesn't include form parameters
+ - fix: Errors generated in webgui.log when viewing last thread
 
 7.4.5
  - fix: Apostrophy incorrectly escaped as double quote in some places

lib/WebGUI/Asset/Post/Thread.pm

@@ -265,7 +265,9 @@ sub getNextThread {
 				group by assetData.assetId
 				order by ".$sortBy." ".$sortOrder." 
 				");
-		$self->{_next} = WebGUI::Asset->new($self->session, $id,$class,$version);
+		if ($id) {
+            $self->{_next} = WebGUI::Asset->new($self->session, $id, $class, $version);
+        }
 	#	delete $self->{_next} unless ($self->{_next}->{_properties}{className} =~ /Thread/);
 	};
 	return $self->{_next};