Make vuex-module-provider do not blow up when used with vue-apollo

- upstream issue: https://github.com/vuejs/vue-apollo/pull/1153

app/assets/javascripts/vue_shared/components/vuex_module_provider.vue

@@ -2,7 +2,10 @@
 export default {
   provide() {
     return {
-      vuexModule: this.vuexModule,
+      // We can't use this.vuexModule due to bug in vue-apollo when
+      // provide is called in beforeCreate
+      // See https://github.com/vuejs/vue-apollo/pull/1153 for details
+      vuexModule: this.$options.propsData.vuexModule,
     };
   },
   props: {

spec/frontend/vue_shared/components/vuex_module_provider_spec.js

-import { mount } from '@vue/test-utils';
+import { mount, createLocalVue } from '@vue/test-utils';
 import Vue from 'vue';
+import VueApollo from 'vue-apollo';
 import VuexModuleProvider from '~/vue_shared/components/vuex_module_provider.vue';
 
 const TestComponent = Vue.extend({
@@ -14,7 +15,7 @@ describe('~/vue_shared/components/vuex_module_provider', () => {
 
   const findProvidedVuexModule = () => wrapper.find('[data-testid="vuexModule"]').text();
 
-  beforeEach(() => {
+  const createComponent = (extraParams = {}) => {
     wrapper = mount(VuexModuleProvider, {
       propsData: {
         vuexModule: TEST_VUEX_MODULE,
@@ -22,10 +23,25 @@ describe('~/vue_shared/components/vuex_module_provider', () => {
       slots: {
         default: TestComponent,
       },
+      ...extraParams,
     });
+  };
+
+  afterEach(() => {
+    wrapper.destroy();
   });
 
   it('provides "vuexModule" set from prop', () => {
+    createComponent();
+    expect(findProvidedVuexModule()).toBe(TEST_VUEX_MODULE);
+  });
+
+  it('does not blow up when used with vue-apollo', () => {
+    // See https://github.com/vuejs/vue-apollo/pull/1153 for details
+    const localVue = createLocalVue();
+    localVue.use(VueApollo);
+
+    createComponent({ localVue });
     expect(findProvidedVuexModule()).toBe(TEST_VUEX_MODULE);
   });
 });