src/vs/workbench/browser/parts/editor/editorsObserver.ts/EditorsObserver/saveState
class EditorsObserver:	private saveState(): void {
		if (this.mostRecentEditorsMap.isEmpty()) {
			this.storageService.remove(EditorsObserver.STORAGE_KEY, StorageScope.WORKSPACE);
		} else {
			this.storageService.store(EditorsObserver.STORAGE_KEY, JSON.stringify(this.serialize()), StorageScope.WORKSPACE, StorageTarget.MACHINE);
		}
	}