119602: Fix SSR error by making klaroService optional

KlaroService handles cookies which are not applicable during SSR. By
making the service optional, and handling the case when it is not
available, SSR can do its work without throwing NullInjectorErrors.

src/app/info/accessibility-settings/accessibility-settings.component.ts

@@ -3,6 +3,7 @@ import {
   Component,
   OnDestroy,
   OnInit,
+  Optional,
 } from '@angular/core';
 import { FormsModule } from '@angular/forms';
 import {
@@ -30,7 +31,10 @@ import { AuthService } from '../../core/auth/auth.service';
 import { AlertComponent } from '../../shared/alert/alert.component';
 import { ContextHelpDirective } from '../../shared/context-help.directive';
 import { KlaroService } from '../../shared/cookies/klaro.service';
-import { isEmpty } from '../../shared/empty.util';
+import {
+  hasValue,
+  isEmpty,
+} from '../../shared/empty.util';
 import { NotificationsService } from '../../shared/notifications/notifications.service';
 
 /**
@@ -65,7 +69,7 @@ export class AccessibilitySettingsComponent implements OnInit, OnDestroy {
     protected settingsService: AccessibilitySettingsService,
     protected notificationsService: NotificationsService,
     protected translateService: TranslateService,
-    protected klaroService: KlaroService,
+    @Optional() protected klaroService: KlaroService,
   ) {
   }
 
@@ -75,11 +79,19 @@ export class AccessibilitySettingsComponent implements OnInit, OnDestroy {
     this.subscriptions.push(
       this.authService.isAuthenticated().pipe(distinctUntilChanged())
         .subscribe(val => this.isAuthenticated.next(val)),
-      this.klaroService.getSavedPreferences().pipe(
-        map(preferences => preferences?.accessibility === true),
-        distinctUntilChanged(),
-      ).subscribe(val => this.cookieIsAccepted.next(val)),
     );
+
+    if (hasValue(this.klaroService)) {
+      this.subscriptions.push(
+        this.klaroService.getSavedPreferences().pipe(
+          map(preferences => preferences?.accessibility === true),
+          distinctUntilChanged(),
+        ).subscribe(val => this.cookieIsAccepted.next(val)),
+      );
+    } else {
+      this.cookieIsAccepted.next(false);
+    }
+
   }
 
   ngOnDestroy() {