MOBILE-2795 data: Fix undefined contents console error

src/addon/mod/data/pages/entry/entry.html

@@ -22,7 +22,7 @@
             </ion-select>
         </ion-item>
 
-        <div class="addon-data-contents {{cssClass}}">
+        <div class="addon-data-contents {{cssClass}}" *ngIf="entry">
             <style *ngIf="cssTemplate">
                 {{ cssTemplate }}
             </style>

src/addon/mod/data/pages/entry/entry.ts

@@ -215,6 +215,7 @@ export class AddonModDataEntryPage implements OnDestroy {
      */
     gotoEntry(entry: number): Promise<any> {
         this.entryId = entry;
+        this.entry = null;
         this.page = null;
         this.entryLoaded = false;