[ADF-2625] updating viewer on node editing (#3160)

* update viewer on metadata changes

* add test and docs

lib/core/services/alfresco-api.service.spec.ts

@@ -0,0 +1,39 @@
+/*!
+ * @license
+ * Copyright 2016 Alfresco Software, Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+import { AlfrescoApiService } from './alfresco-api.service';
+
+describe('AlfrescoApiService', () => {
+
+    let service: AlfrescoApiService;
+
+    beforeEach(() => {
+        service = new AlfrescoApiService(null, null);
+    });
+
+    it('should rase nodeChanged event with node payload', (done) => {
+        const node: any = {};
+
+        service.nodeUpdated.subscribe(result => {
+            expect(result).toEqual(node);
+            done();
+        });
+
+        service.nodeUpdated.next(node);
+    });
+
+});