Render user avatar image using `GlAvatar`

This is added behind the FF which is introduced in this MR

app/assets/javascripts/vue_shared/components/user_avatar/user_avatar_image.vue

 <script>
 /* This is a re-usable vue component for rendering a user avatar that
-  does not need to link to the user's profile. The image and an optional
-  tooltip can be configured by props passed to this component.
+    does not need to link to the user's profile. The image and an optional
+    tooltip can be configured by props passed to this component.
 
-  Sample configuration:
+    Sample configuration:
 
-  <user-avatar-image
-    :lazy="true"
-    :img-src="userAvatarSrc"
-    :img-alt="tooltipText"
-    :tooltip-text="tooltipText"
-    tooltip-placement="top"
-  />
+    <user-avatar-image
+      lazy
+      :img-src="userAvatarSrc"
+      :img-alt="tooltipText"
+      :tooltip-text="tooltipText"
+      tooltip-placement="top"
+    />
 
-*/
+  */
 
-import { GlTooltip } from '@gitlab/ui';
+import { GlTooltip, GlAvatar } from '@gitlab/ui';
 import defaultAvatarUrl from 'images/no_avatar.png';
 import { __ } from '~/locale';
+import glFeatureFlagMixin from '~/vue_shared/mixins/gl_feature_flags_mixin';
 import { placeholderImage } from '../../../lazy_loader';
 
 export default {
   name: 'UserAvatarImage',
   components: {
     GlTooltip,
+    GlAvatar,
   },
+  mixins: [glFeatureFlagMixin()],
   props: {
     lazy: {
       type: Boolean,
@@ -85,7 +88,20 @@ export default {
 
 <template>
   <span>
+    <gl-avatar
+      v-if="glFeatures.glAvatarForAllUserAvatars"
+      ref="userAvatarImage"
+      :class="{
+        lazy: lazy,
+        [cssClasses]: true,
+      }"
+      :src="resultantSrcAttribute"
+      :data-src="sanitizedSource"
+      :size="size"
+      :alt="imgAlt"
+    />
     <img
+      v-else
       ref="userAvatarImage"
       :class="{
         lazy: lazy,
@@ -100,11 +116,9 @@ export default {
       class="avatar"
     />
     <gl-tooltip
-      v-if="tooltipText || $slots.default"
       :target="() => $refs.userAvatarImage"
       :placement="tooltipPlacement"
       boundary="window"
-      class="js-user-avatar-image-tooltip"
     >
       <slot> {{ tooltipText }} </slot>
     </gl-tooltip>

config/feature_flags/development/gl_avatar_for_all_user_avatars.yml

+---
+name: gl_avatar_for_all_user_avatars
+introduced_by_url: https://gitlab.com/gitlab-org/gitlab/-/merge_requests/81437
+rollout_issue_url: https://gitlab.com/gitlab-org/gitlab/-/issues/353477
+milestone: '14.9'
+type: development
+group: group::foundations
+default_enabled: false

ee/spec/features/merge_requests/user_resets_approvers_spec.rb

@@ -17,6 +17,7 @@ RSpec.describe 'Merge Requests > User resets approvers', :js do
 
   before do
     stub_licensed_features(multiple_approval_rules: true)
+    stub_feature_flags(gl_avatar_for_all_user_avatars: false)
 
     project_approvers.each do |approver|
       project.add_developer(approver)

ee/spec/features/projects/settings/merge_request_approvals_settings_spec.rb

@@ -18,6 +18,7 @@ RSpec.describe 'Project settings > [EE] Merge Request Approvals', :js do
     project.add_maintainer(user)
     group.add_developer(user)
     group.add_developer(group_member)
+    stub_feature_flags(gl_avatar_for_all_user_avatars: false)
   end
 
   it 'adds approver' do

lib/gitlab/gon_helper.rb

@@ -59,6 +59,7 @@ module Gitlab
       push_frontend_feature_flag(:bootstrap_confirmation_modals, default_enabled: :yaml)
       push_frontend_feature_flag(:sandboxed_mermaid, default_enabled: :yaml)
       push_frontend_feature_flag(:source_editor_toolbar, default_enabled: :yaml)
+      push_frontend_feature_flag(:gl_avatar_for_all_user_avatars, default_enabled: :yaml)
     end
 
     # Exposes the state of a feature flag to the frontend code.

spec/features/boards/boards_spec.rb

@@ -23,6 +23,7 @@ RSpec.describe 'Project issue boards', :js do
       project.add_maintainer(user2)
 
       sign_in(user)
+      stub_feature_flags(gl_avatar_for_all_user_avatars: false)
 
       set_cookie('sidebar_collapsed', 'true')
     end

spec/features/merge_request/user_sees_avatar_on_diff_notes_spec.rb

@@ -25,6 +25,7 @@ RSpec.describe 'Merge request > User sees avatars on diff notes', :js do
   before do
     project.add_maintainer(user)
     sign_in user
+    stub_feature_flags(gl_avatar_for_all_user_avatars: false)
 
     set_cookie('sidebar_collapsed', 'true')
   end

spec/frontend/vue_shared/components/user_avatar/user_avatar_image_spec.js

 import { shallowMount } from '@vue/test-utils';
+import { GlAvatar, GlTooltip } from '@gitlab/ui';
 import defaultAvatarUrl from 'images/no_avatar.png';
 import { placeholderImage } from '~/lazy_loader';
 import UserAvatarImage from '~/vue_shared/components/user_avatar/user_avatar_image.vue';
 
 jest.mock('images/no_avatar.png', () => 'default-avatar-url');
 
-const DEFAULT_PROPS = {
-  size: 99,
+const PROVIDED_PROPS = {
+  size: 32,
   imgSrc: 'myavatarurl.com',
   imgAlt: 'mydisplayname',
   cssClasses: 'myextraavatarclass',
@@ -14,6 +15,10 @@ const DEFAULT_PROPS = {
   tooltipPlacement: 'bottom',
 };
 
+const DEFAULT_PROPS = {
+  size: 20,
+};
+
 describe('User Avatar Image Component', () => {
   let wrapper;
 
@@ -21,64 +26,149 @@ describe('User Avatar Image Component', () => {
     wrapper.destroy();
   });
 
-  describe('Initialization', () => {
-    beforeEach(() => {
-      wrapper = shallowMount(UserAvatarImage, {
-        propsData: {
-          ...DEFAULT_PROPS,
-        },
+  describe('`glAvatarForAllUserAvatars` feature flag enabled', () => {
+    describe('Initialization', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage, {
+          propsData: {
+            ...PROVIDED_PROPS,
+          },
+          provide: {
+            glFeatures: {
+              glAvatarForAllUserAvatars: true,
+            },
+          },
+        });
+      });
+
+      it('should render `GlAvatar` and provide correct properties to it', () => {
+        const avatar = wrapper.findComponent(GlAvatar);
+
+        expect(avatar.attributes('data-src')).toBe(
+          `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+        );
+        expect(avatar.props()).toMatchObject({
+          src: `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+          alt: PROVIDED_PROPS.imgAlt,
+        });
+      });
+
+      it('should add correct CSS classes', () => {
+        const classes = wrapper.findComponent(GlAvatar).classes();
+        expect(classes).toContain(PROVIDED_PROPS.cssClasses);
+        expect(classes).not.toContain('lazy');
       });
     });
 
-    it('should have <img> as a child element', () => {
-      const imageElement = wrapper.find('img');
+    describe('Initialization when lazy', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage, {
+          propsData: {
+            ...PROVIDED_PROPS,
+            lazy: true,
+          },
+          provide: {
+            glFeatures: {
+              glAvatarForAllUserAvatars: true,
+            },
+          },
+        });
+      });
+
+      it('should add lazy attributes', () => {
+        const avatar = wrapper.findComponent(GlAvatar);
 
-      expect(imageElement.exists()).toBe(true);
-      expect(imageElement.attributes('src')).toBe(`${DEFAULT_PROPS.imgSrc}?width=99`);
-      expect(imageElement.attributes('data-src')).toBe(`${DEFAULT_PROPS.imgSrc}?width=99`);
-      expect(imageElement.attributes('alt')).toBe(DEFAULT_PROPS.imgAlt);
+        expect(avatar.classes()).toContain('lazy');
+        expect(avatar.attributes()).toMatchObject({
+          src: placeholderImage,
+          'data-src': `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+        });
+      });
     });
 
-    it('should properly render img css', () => {
-      const classes = wrapper.find('img').classes();
-      expect(classes).toEqual(expect.arrayContaining(['avatar', 's99', DEFAULT_PROPS.cssClasses]));
-      expect(classes).not.toContain('lazy');
+    describe('Initialization without src', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage);
+      });
+
+      it('should have default avatar image', () => {
+        const imageElement = wrapper.find('img');
+
+        expect(imageElement.attributes('src')).toBe(
+          `${defaultAvatarUrl}?width=${DEFAULT_PROPS.size}`,
+        );
+      });
     });
   });
 
-  describe('Initialization when lazy', () => {
-    beforeEach(() => {
-      wrapper = shallowMount(UserAvatarImage, {
-        propsData: {
-          ...DEFAULT_PROPS,
-          lazy: true,
-        },
+  describe('`glAvatarForAllUserAvatars` feature flag disabled', () => {
+    describe('Initialization', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage, {
+          propsData: {
+            ...PROVIDED_PROPS,
+          },
+        });
       });
-    });
 
-    it('should add lazy attributes', () => {
-      const imageElement = wrapper.find('img');
+      it('should have <img> as a child element', () => {
+        const imageElement = wrapper.find('img');
+
+        expect(imageElement.exists()).toBe(true);
+        expect(imageElement.attributes('src')).toBe(
+          `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+        );
+        expect(imageElement.attributes('data-src')).toBe(
+          `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+        );
+        expect(imageElement.attributes('alt')).toBe(PROVIDED_PROPS.imgAlt);
+      });
 
-      expect(imageElement.classes()).toContain('lazy');
-      expect(imageElement.attributes('src')).toBe(placeholderImage);
-      expect(imageElement.attributes('data-src')).toBe(`${DEFAULT_PROPS.imgSrc}?width=99`);
+      it('should properly render img css', () => {
+        const classes = wrapper.find('img').classes();
+        expect(classes).toEqual(['avatar', 's32', PROVIDED_PROPS.cssClasses]);
+        expect(classes).not.toContain('lazy');
+      });
     });
-  });
 
-  describe('Initialization without src', () => {
-    beforeEach(() => {
-      wrapper = shallowMount(UserAvatarImage);
+    describe('Initialization when lazy', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage, {
+          propsData: {
+            ...PROVIDED_PROPS,
+            lazy: true,
+          },
+        });
+      });
+
+      it('should add lazy attributes', () => {
+        const imageElement = wrapper.find('img');
+
+        expect(imageElement.classes()).toContain('lazy');
+        expect(imageElement.attributes('src')).toBe(placeholderImage);
+        expect(imageElement.attributes('data-src')).toBe(
+          `${PROVIDED_PROPS.imgSrc}?width=${PROVIDED_PROPS.size}`,
+        );
+      });
     });
 
-    it('should have default avatar image', () => {
-      const imageElement = wrapper.find('img');
+    describe('Initialization without src', () => {
+      beforeEach(() => {
+        wrapper = shallowMount(UserAvatarImage);
+      });
+
+      it('should have default avatar image', () => {
+        const imageElement = wrapper.find('img');
 
-      expect(imageElement.attributes('src')).toBe(`${defaultAvatarUrl}?width=20`);
+        expect(imageElement.attributes('src')).toBe(
+          `${defaultAvatarUrl}?width=${DEFAULT_PROPS.size}`,
+        );
+      });
     });
   });
 
   describe('dynamic tooltip content', () => {
-    const props = DEFAULT_PROPS;
+    const props = PROVIDED_PROPS;
     const slots = {
       default: ['Action!'],
     };
@@ -91,11 +181,11 @@ describe('User Avatar Image Component', () => {
     });
 
     it('renders the tooltip slot', () => {
-      expect(wrapper.find('.js-user-avatar-image-tooltip').exists()).toBe(true);
+      expect(wrapper.findComponent(GlTooltip).exists()).toBe(true);
     });
 
     it('renders the tooltip content', () => {
-      expect(wrapper.find('.js-user-avatar-image-tooltip').text()).toContain(slots.default[0]);
+      expect(wrapper.findComponent(GlTooltip).text()).toContain(slots.default[0]);
     });
 
     it('does not render tooltip data attributes for on avatar image', () => {