message: Fixed translation error
diff: <span class="spacer"></span>
  <span class="lightgray"> {{unitDesc}} </span>
  <mat-checkbox *ngIf="!this.showDL" [(ngModel)]="chkbox" (change)="emitEvent()" class="chkbox"></mat-checkbox>
  - <button mat-icon-button color="primary" *ngIf="this.showDL" class="dlButton" (click)="this.downloadFile()" matTooltip="{{ common.tooltipDownloadUnit | translate}}">
  + <button mat-icon-button color="primary" *ngIf="this.showDL" class="dlButton" (click)="this.downloadFile()" matTooltip="Download">
  <mat-icon>file_download</mat-icon>
  </button>
  </mat-list-item>
  