--- a/toolkit/components/url-classifier/SafeBrowsing.jsm
+++ b/toolkit/components/url-classifier/SafeBrowsing.jsm
@@ -334,16 +334,19 @@ this.SafeBrowsing = {
         } else {
           providerStr += ", " + provider;
         }
       });
       log("Providers: " + providerStr);
     }
 
     Object.keys(this.providers).forEach(function(provider) {
+      if (provider == "test") {
+        return; // skip
+      }
       let updateURL = Services.urlFormatter.formatURLPref(
         "browser.safebrowsing.provider." + provider + ".updateURL");
       let gethashURL = Services.urlFormatter.formatURLPref(
         "browser.safebrowsing.provider." + provider + ".gethashURL");
       updateURL = updateURL.replace("SAFEBROWSING_ID", clientID);
       gethashURL = gethashURL.replace("SAFEBROWSING_ID", clientID);
 
       // Disable updates and gethash if the Google API key is missing.

--- a/toolkit/components/url-classifier/tests/unit/test_bug1274685_unowned_list.js
+++ b/toolkit/components/url-classifier/tests/unit/test_bug1274685_unowned_list.js
@@ -4,28 +4,31 @@ ChromeUtils.import("resource://testing-c
 // 'Cc["@mozilla.org/xre/app-info;1"]' for xpcshell has no nsIXULAppInfo
 // so that we have to update it to make nsURLFormatter.js happy.
 // (SafeBrowsing.init() will indirectly use nsURLFormatter.js)
 updateAppInfo();
 
 function run_test() {
   SafeBrowsing.init();
 
-  let origList = Services.prefs.getCharPref("browser.safebrowsing.provider.google.lists");
+  let origListV2 = Services.prefs.getCharPref("browser.safebrowsing.provider.google.lists");
+  let origListV4 = Services.prefs.getCharPref("browser.safebrowsing.provider.google4.lists");
 
-  // Remove 'goog-malware-shavar' from the original.
-  let trimmedList = origList.replace("goog-malware-shavar,", "");
-  Services.prefs.setCharPref("browser.safebrowsing.provider.google.lists", trimmedList);
+  // Ensure there's a list missing in both Safe Browsing V2 and V4.
+  let trimmedListV2 = origListV2.replace("goog-malware-shavar,", "");
+  Services.prefs.setCharPref("browser.safebrowsing.provider.google.lists", trimmedListV2);
+  let trimmedListV4 = origListV4.replace("goog-malware-proto,", "");
+  Services.prefs.setCharPref("browser.safebrowsing.provider.google4.lists", trimmedListV4);
 
   try {
     // Bug 1274685 - Unowned Safe Browsing tables break list updates
     //
     // If SafeBrowsing.registerTableWithURLs() doesn't check if
     // a provider is found before registering table, an exception
     // will be thrown while accessing a null object.
     //
     SafeBrowsing.registerTables();
   } catch (e) {
     ok(false, "Exception thrown due to " + e.toString());
   }
-
-  Services.prefs.setCharPref("browser.safebrowsing.provider.google.lists", origList);
+  Services.prefs.clearUserPref("browser.safebrowsing.provider.google.lists");
+  Services.prefs.clearUserPref("browser.safebrowsing.provider.google4.lists");
 }