src/vs/platform/configuration/common/configurationModels.ts/ConfigurationChangeEvent/constructor
class ConfigurationChangeEvent:	constructor(readonly change: IConfigurationChange, private readonly previous: { workspace?: Workspace; data: IConfigurationData } | undefined, private readonly currentConfiguraiton: Configuration, private readonly currentWorkspace?: Workspace) {
		const keysSet = new Set<string>();
		change.keys.forEach(key => keysSet.add(key));
		change.overrides.forEach(([, keys]) => keys.forEach(key => keysSet.add(key)));
		this.affectedKeys = [...keysSet.values()];

		const configurationModel = new ConfigurationModel();
		this.affectedKeys.forEach(key => configurationModel.setValue(key, {}));
		this.affectedKeysTree = configurationModel.contents;
	}