src/vs/workbench/api/common/shared/dataTransferCache.ts/DataTransferCache/add
class DataTransferCache:	public add(dataTransfer: VSDataTransfer): { id: number; dispose: () => void } {
		const requestId = this.requestIdPool++;
		this.dataTransfers.set(requestId, [...dataTransfer.values()]);
		return {
			id: requestId,
			dispose: () => {
				this.dataTransfers.delete(requestId);
			}
		};
	}