feat: add option not to display media error

In the context of using gallery as a generic slider, where using custom
items is very probable, having a state for media loading error makes
little sense, so an option to turn it off is needed.

libs/gallery/src/lib/components/gallery/gallery.component.html

@@ -26,6 +26,7 @@
   [arrows]="arrows"
   [descriptions]="descriptions"
   [errorText]="errorText"
+  [showErrors]="showErrors"
   [mouseGestures]="mouseGestures"
   [touchGestures]="touchGestures"
   [clip]="clip"

libs/gallery/src/lib/components/gallery/gallery.component.ts

@@ -61,6 +61,10 @@ export class GalleryComponent {
    * Text to be shown when media loading failed
    */
   @Input() errorText: string;
+  /**
+   * Display an error when the media contained in gallery item failed to load.
+   */
+  @Input() showErrors = false;
   /**
    * Allow mouse swipes
    */

libs/gallery/src/lib/components/viewer/viewer.component.simple.spec.ts

@@ -59,6 +59,7 @@ describe('ViewerComponent', () => {
       ]);
       viewer = new ViewerComponent(null, changeDetector, null, null);
       viewer.items = [{ src: 'src1' }, { src: 'src2' }];
+      viewer.showErrors = true;
     });
 
     describe('failed', () => {

libs/gallery/src/lib/components/viewer/viewer.component.ts

@@ -71,6 +71,7 @@ export class ViewerComponent implements OnChanges, OnInit, AfterViewInit {
   @Input() selectedIndex: number;
   @Input() descriptions: boolean;
   @Input() errorText: string;
+  @Input() showErrors: boolean;
   @Input() mouseGestures: boolean;
   @Input() touchGestures: boolean;
   @Input() counter: boolean;
@@ -254,6 +255,9 @@ export class ViewerComponent implements OnChanges, OnInit, AfterViewInit {
   }
 
   onItemErrored(item: GalleryItemInternal) {
+    if (!this.showErrors) {
+      return;
+    }
     item._failed = true;
     this._cd.detectChanges();
   }