src/vs/workbench/browser/dnd.ts/ResourceListDnDHandler/onDragStart
class ResourceListDnDHandler:	onDragStart(data: IDragAndDropData, originalEvent: DragEvent): void {
		const resources: URI[] = [];
		for (const element of (data as ElementsDragAndDropData<T>).elements) {
			const resource = this.toResource(element);
			if (resource) {
				resources.push(resource);
			}
		}
		if (resources.length) {
			// Apply some datatransfer types to allow for dragging the element outside of the application
			this.instantiationService.invokeFunction(accessor => fillEditorsDragData(accessor, resources, originalEvent));
		}
	}