src/vs/workbench/services/workingCopy/common/workingCopyBackupTracker.ts/WorkingCopyBackupTracker/discardBackup
class WorkingCopyBackupTracker:	private discardBackup(workingCopy: IWorkingCopy): void {

		// Clear any running backup operation
		this.cancelBackupOperation(workingCopy);

		// Schedule backup discard asap
		const workingCopyIdentifier = { resource: workingCopy.resource, typeId: workingCopy.typeId };
		const cts = new CancellationTokenSource();
		this.doDiscardBackup(workingCopyIdentifier, cts);

		// Keep in map for disposal as needed
		this.pendingBackupOperations.set(workingCopyIdentifier, toDisposable(() => {
			this.logService.trace(`[backup tracker] clearing pending backup discard`, workingCopy.resource.toString(), workingCopy.typeId);

			cts.dispose(true);
		}));
	}