src/vs/workbench/contrib/tasks/common/tasks.ts/InMemoryTask/constructor
class InMemoryTask:	public constructor(id: string, source: InMemoryTaskSource, label: string, type: string,
		runOptions: RunOptions, configurationProperties: ConfigurationProperties) {
		super(id, label, type, runOptions, configurationProperties, source);
		this._source = source;
	}