Fix for failing test with Chrome debugging

A new error popped up ("LinkView is not attached") which required a more generalized check.

lib/browser/util.js

@@ -107,7 +107,7 @@ export function createCollection(prototype, realmId, info, mutable) {
             resize();
         } catch (e) {
             // If the error indicates the list was deleted, then remove this listener.
-            if (e.message == 'Tableview is not attached') {
+            if (e.message.indexOf('is not attached') > 0) {
                 removeMutationListener(realmId, listener);
             } else {
                 throw e;