src/vs/platform/extensionManagement/common/extensionStorage.ts/ExtensionStorageService/migrationList
class ExtensionStorageService:	private set migrationList(migrationList: [string, string][]) {
		if (migrationList.length) {
			this.storageService.store('extensionStorage.migrationList', JSON.stringify(migrationList), StorageScope.APPLICATION, StorageTarget.MACHINE);
		} else {
			this.storageService.remove('extensionStorage.migrationList', StorageScope.APPLICATION);
		}
	}