Added blank members access settings screen behind dev flag

refs https://github.com/TryGhost/Team/issues/579

- empty screen ready for signup access and default post access level settings to be moved to
- has unsaved settings changes modal ready

ghost/admin/app/controllers/settings/members-access.js

@@ -0,0 +1,37 @@
+import Controller from '@ember/controller';
+import {action} from '@ember/object';
+import {inject as service} from '@ember/service';
+import {task} from 'ember-concurrency-decorators';
+import {tracked} from '@glimmer/tracking';
+
+export default class MembersAccessController extends Controller {
+    @service settings;
+
+    @tracked showLeaveSettingsModal = false;
+
+    leaveRoute(transition) {
+        if (this.settings.get('hasDirtyAttributes')) {
+            transition.abort();
+            this.leaveSettingsTransition = transition;
+            this.showLeaveSettingsModal = true;
+        }
+    }
+
+    @action
+    async confirmLeave() {
+        this.settings.rollbackAttributes();
+        this.showLeaveSettingsModal = false;
+        this.leaveSettingsTransition.retry();
+    }
+
+    @action
+    cancelLeave() {
+        this.showLeaveSettingsModal = false;
+        this.leaveSettingsTransition = null;
+    }
+
+    @task({drop: true})
+    *saveSettingsTask() {
+        return yield this.settings.save();
+    }
+}

ghost/admin/app/router.js

@@ -48,6 +48,7 @@ Router.map(function () {
 
     this.route('settings');
     this.route('settings.general', {path: '/settings/general'});
+    this.route('settings.members-access', {path: '/settings/members-access'});
     this.route('settings.members-email', {path: '/settings/members-email'});
     this.route('settings.members-payments', {path: '/settings/members-payments'});
     this.route('settings.code-injection', {path: '/settings/code-injection'});

ghost/admin/app/routes/settings/members-access.js

@@ -0,0 +1,22 @@
+import AuthenticatedRoute from 'ghost-admin/routes/authenticated';
+import {inject as service} from '@ember/service';
+
+export default class MembersAccessRoute extends AuthenticatedRoute {
+    @service settings;
+
+    model() {
+        this.settings.reload();
+    }
+
+    actions = {
+        willTransition(transition) {
+            return this.controller.leaveRoute(transition);
+        }
+    }
+
+    buildRouteInfoMetadata() {
+        return {
+            titleToken: 'Settings - Members'
+        };
+    }
+}

ghost/admin/app/templates/settings.hbs

@@ -40,6 +40,15 @@
 
         <div class="gh-setting-header">Members</div>
         <div class="gh-settings-main-grid">
+            {{#if (enable-developer-experiments)}}
+                <LinkTo class="gh-setting-group" @route="settings.members-access" data-test-nav="members-access">
+                    <span class="color-3">{{svg-jar "portal-logo-stroke"}}</span>
+                    <div>
+                        <h4>Access</h4>
+                        <p>Configure members usage and default access levels</p>
+                    </div>
+                </LinkTo>
+            {{/if}}
             <button type="button" class="gh-setting-group portal" {{action (toggle "showPortalSettings" this)}} data-test-toggle-membersFrom>
                 <span class="color-3">{{svg-jar "portal-logo-stroke"}}</span>
                 <div>

ghost/admin/app/templates/settings/members-access.hbs

@@ -0,0 +1,31 @@
+<section class="gh-canvas">
+    <GhCanvasHeader class="gh-canvas-header">
+        <h2 class="gh-canvas-title" data-test-screen-title>
+            <LinkTo @route="settings">Settings</LinkTo>
+            <span>{{svg-jar "arrow-right"}}</span>
+            Access
+        </h2>
+        <section class="view-actions">
+            <GhTaskButton @buttonText="Save settings"
+                @task={{this.saveSettingsTask}}
+                @successText="Saved"
+                @runningText="Saving"
+                @class="gh-btn gh-btn-primary gh-btn-icon"
+                data-test-button="save-settings"
+            />
+        </section>
+    </GhCanvasHeader>
+
+    <section class="view-container settings-debug">
+
+    </section>
+
+    {{#if this.showLeaveSettingsModal}}
+        <GhFullscreenModal
+            @modal="leave-settings"
+            @confirm={{this.confirmLeave}}
+            @close={{this.cancelLeave}}
+            @modifier="action wide"
+        />
+    {{/if}}
+</section>