[ACA-2782] Header - sidenav menu button expanded/collapsed state not exposed via ARIA (#1239)

* Implement the expanded aria for the sidenav toogle button

src/app/components/header/header.component.html

@@ -5,6 +5,7 @@
   [color]="headerColor$ | async"
   [title]="appName$ | async"
   (clicked)="toggleClicked.emit($event)"
+  [expandedSidenav]="expandedSidenav"
 >
   <div class="adf-toolbar--spacer adf-toolbar-divider"></div>
 

src/app/components/header/header.component.ts

@@ -28,7 +28,8 @@ import {
   ViewEncapsulation,
   Output,
   EventEmitter,
-  OnInit
+  OnInit,
+  Input
 } from '@angular/core';
 import { Store } from '@ngrx/store';
 import { Observable } from 'rxjs';
@@ -51,6 +52,8 @@ export class AppHeaderComponent implements OnInit {
   @Output()
   toggleClicked = new EventEmitter();
 
+  @Input() expandedSidenav = true;
+
   appName$: Observable<string>;
   headerColor$: Observable<string>;
   logo$: Observable<string>;