src/vs/editor/common/model/textModel.ts/TextModel/getLineDecorations
class TextModel:	public getLineDecorations(lineNumber: number, ownerId: number = 0, filterOutValidation: boolean = false): model.IModelDecoration[] {
		if (lineNumber < 1 || lineNumber > this.getLineCount()) {
			return [];
		}
		return this.getLinesDecorations(lineNumber, lineNumber, ownerId, filterOutValidation);
	}