amend some weekness according code review

app/assets/javascripts/sidebar/components/subscriptions/subscriptions.vue

@@ -29,7 +29,7 @@ export default {
     projectEmailsDisabled: {
       type: Boolean,
       required: false,
-      default: null,
+      default: false,
     },
     subscribeDisabledDescription: {
       type: String,
@@ -65,7 +65,7 @@ export default {
     },
     notificationText() {
       if (this.projectEmailsDisabled) {
-        return __(this.subscribeDisabledDescription);
+        return this.subscribeDisabledDescription;
       }
       return __('Notifications');
     },
@@ -120,7 +120,7 @@ export default {
     </span>
     <span class="issuable-header-text hide-collapsed float-left"> {{ notificationText }} </span>
     <toggle-button
-      v-if="projectEmailsDisabled != true"
+      v-if="!projectEmailsDisabled"
       ref="toggleButton"
       :is-loading="showLoadingState"
       :value="subscribed"

app/serializers/issuable_sidebar_extras_entity.rb

@@ -13,7 +13,7 @@ class IssuableSidebarExtrasEntity < Grape::Entity
     issuable.project.emails_disabled?
   end
 
-  expose :subscribe_disabled_description do |issuable|
+  expose :subscribe_disabled_description do
     notification_description(:owner_disabled)
   end
 

changelogs/unreleased/31184-refactor-disabled-sidebar-notification-to-vue.yml

 ---
 title: Refactor disabled sidebar notifications to Vue
-merge_request: !19532
+merge_request: 20007
 author: minghuan lei
-type: deprecated
+type: other