[mv3] Fix toggling of "no filtering" as default mode

A bad test prevented the "no filtering" by default mode to not take
effect immediately when activated while no site had yet been set to
"no filtering". It would however take effect as soon as a specific
site would be excluded from "no filtering".

Author: gorhill

platform/mv3/extension/js/ruleset-manager.js

@@ -559,16 +559,17 @@ async function filteringModesToDNR(modes) {
     return Promise.all(promises);
 }
 
-const isDifferentAllowRules = (a, b) => {
+const isDifferentAllowRules = (a = [], b = []) => {
+    if ( a.length !== b.length ) { return true; }
     const pp = [
         'requestDomains',
         'excludedRequestDomains',
         'initiatorDomains',
         'excludedInitiatorDomains',
     ];
     for ( const p of pp ) {
-        const ac = a?.length && a[0].condition[p] || [];
-        const bc = b?.length && b[0].condition[p] || [];
+        const ac = a.length && a[0].condition[p] || [];
+        const bc = b.length && b[0].condition[p] || [];
         if ( ac.join() !== bc.join() ) { return true; }
     }
     return false;