message: Fix drop listener for file question in knockout, when jquery is not available
diff: @@ -22,7 +22,7 @@ export class QuestionFileImplementor extends QuestionImplementor {
  (<any>this.question)["koData"] = this.koData;
  (<any>this.question)["koHasValue"] = this.koHasValue;
  (<any>this.question)["koInputTitle"] = this.koInputTitle;
  - (<any>this.question)["koFileClass"] = this.koFileRootClass;
  + (<any>this.question)["koFileRootClass"] = this.koFileRootClass;
  this.koFileRootClass(this.question.cssClasses.root);
  var updateState = (state: any) => {
  this.koState(state);
  @@ -34,7 +34,9 @@ export class QuestionFileImplementor extends QuestionImplementor {
  (<any>this.question)["ondrop"] = (data: any, event: any) => {
  event.preventDefault();
  this.unhighlight();
  - let src = event.originalEvent.dataTransfer;
  + let src = event.originalEvent
  + ? event.originalEvent.dataTransfer
  + : event.dataTransfer;
  this.onChange(src);
  };
  (<any>this.question)["ondragover"] = (data: any, event: any) => {
  