src/vs/workbench/contrib/preferences/common/preferencesContribution.ts/PreferencesContribution/getSchemaModel
class PreferencesContribution:	private getSchemaModel(uri: URI): ITextModel | null {
		let schema = schemaRegistry.getSchemaContributions().schemas[uri.toString()];
		if (schema) {
			const modelContent = JSON.stringify(schema);
			const languageSelection = this.languageService.createById('jsonc');
			const model = this.modelService.createModel(modelContent, languageSelection, uri);
			const disposables = new DisposableStore();
			disposables.add(schemaRegistry.onDidChangeSchema(schemaUri => {
				if (schemaUri === uri.toString()) {
					schema = schemaRegistry.getSchemaContributions().schemas[uri.toString()];
					model.setValue(JSON.stringify(schema));
				}
			}));
			disposables.add(model.onWillDispose(() => disposables.dispose()));

			return model;
		}
		return null;
	}