Migrate epic sidebar todo button to widget

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ee/app/assets/javascripts/epic/components/epic_sidebar.vue

@@ -174,7 +174,7 @@ export default {
     <div class="issuable-sidebar js-issuable-update">
       <sidebar-header :sidebar-collapsed="sidebarCollapsed">
         <sidebar-todo-widget
-          v-show="isUserSignedIn"
+          v-if="isUserSignedIn"
           :issuable-id="fullEpicId"
           :issuable-iid="String(iid)"
           :full-path="fullPath"

ee/spec/frontend/epic/components/epic_sidebar_spec.js

@@ -178,14 +178,6 @@ describe('EpicSidebarComponent', () => {
       expect(wrapper.find('.issuable-sidebar.js-issuable-update').exists()).toBe(true);
     });
 
-    it('renders Todo toggle button element when sidebar is collapsed and user is signed in', async () => {
-      store.dispatch('toggleSidebarFlag', true);
-
-      await nextTick();
-
-      expect(wrapper.find('[data-testid="todo"]').exists()).toBe(true);
-    });
-
     it('renders Start date & Due date elements when sidebar is expanded', async () => {
       wrapper.vm.$store.dispatch('toggleSidebarFlag', false);
 
@@ -215,8 +207,15 @@ describe('EpicSidebarComponent', () => {
       expect(wrapper.find(SidebarSubscriptionsWidget).exists()).toBe(true);
     });
 
-    it('renders SidebarTodoWidget', () => {
-      expect(wrapper.find(SidebarTodoWidget).exists()).toBe(true);
+    it('renders SidebarTodoWidget when user is signed in', () => {
+      const todoWidget = wrapper.find(SidebarTodoWidget);
+      expect(todoWidget.exists()).toBe(true);
+      expect(todoWidget.props()).toMatchObject({
+        issuableId: 'gid://gitlab/Epic/1',
+        issuableIid: '1',
+        fullPath: 'frontend-fixtures-group',
+        issuableType: 'epic',
+      });
     });
 
     it('renders SidebarReferenceWidget', () => {
@@ -259,6 +258,16 @@ describe('EpicSidebarComponent', () => {
     });
   });
 
+  describe('when user is not signed in', () => {
+    beforeEach(() => {
+      gon.current_user_id = null;
+    });
+
+    it('does not render SidebarTodoWidget', () => {
+      expect(wrapper.find(SidebarTodoWidget).exists()).toBe(false);
+    });
+  });
+
   describe('mounted', () => {
     it('makes request to get epic details', () => {
       const actionSpies = {