src/vs/platform/configuration/common/configurationModels.ts/Configuration/updateValue
class Configuration:	updateValue(key: string, value: any, overrides: IConfigurationUpdateOverrides = {}): void {
		let memoryConfiguration: ConfigurationModel | undefined;
		if (overrides.resource) {
			memoryConfiguration = this._memoryConfigurationByResource.get(overrides.resource);
			if (!memoryConfiguration) {
				memoryConfiguration = new ConfigurationModel();
				this._memoryConfigurationByResource.set(overrides.resource, memoryConfiguration);
			}
		} else {
			memoryConfiguration = this._memoryConfiguration;
		}

		if (value === undefined) {
			memoryConfiguration.removeValue(key);
		} else {
			memoryConfiguration.setValue(key, value);
		}

		if (!overrides.resource) {
			this._workspaceConsolidatedConfiguration = null;
		}
	}