src/vs/editor/common/model/pieceTreeTextBuffer/pieceTreeTextBuffer.ts/PieceTreeTextBuffer/getLineLastNonWhitespaceColumn
class PieceTreeTextBuffer:	public getLineLastNonWhitespaceColumn(lineNumber: number): number {
		const result = strings.lastNonWhitespaceIndex(this.getLineContent(lineNumber));
		if (result === -1) {
			return 0;
		}
		return result + 2;
	}