TextArea "heightInLines" stopped working started from SDK 4.1

Interested in your opinion on SDK-26781  "Spark TextArea heightInLines stopped working from SDK 4.0 to stable version 4.1" which is currently closed.

In Flex 4.5.18623 the TextArea behaviour had changed to the following:

TextArea gets sized in height correctly at the start and then during the edit session the height of TextArea suddenly changes to ~1.5 lines with default skin applied.

Code sample to illustrate this issue:

<?xml version="1.0" encoding="utf-8"?> <s:Application xmlns:fx="http://ns.adobe.com/mxml/2009"                xmlns:s="library://ns.adobe.com/flex/spark"                xmlns:mx="library://ns.adobe.com/flex/mx">     <fx:Declarations>         <fx:XML id="data">             <flow:TextFlow xmlns:flow="http://ns.adobe.com/textLayout/2008">             <flow:p>                 <flow:span>There are many such lime-kilns in that tract of country, for the purpose of burning the white marble which composes a large part of the substance of the hills. Some of them, built years ago, and long deserted, with weeds growing in the vacant round of the interior, which is open to the sky, and grass and wild-flowers rooting themselves into the chinks of the stones, look already like relics of antiquity, and may yet be overspread with the lichens of centuries to come. Others, where the lime-burner still feeds his daily and nightlong fire, afford points of interest to the wanderer among the hills, who seats himself on a log of wood or a fragment of marble, to hold a chat with the solitary man. It is a lonesome, and, when the character is inclined to thought, may be an intensely thoughtful occupation; as it proved in the case of Ethan Brand, who had mused to such strange purpose, in days gone by, while the fire in this very kiln was burning.                 </flow:span></flow:p>             </flow:TextFlow>         </fx:XML>     </fx:Declarations>        <s:RichEditableText                id="ret"                width="200"                heightInLines="NaN"         textFlow="{TextConverter.importToFlow(data,TextConverter.TEXT_LAYOUT_FORMAT)}">            </s:RichEditableText>     <s:TextArea id="ta"                 horizontalCenter="0"                 verticalCenter="0"                 heightInLines="NaN"                 textFlow="{TextConverter.importToFlow(data,TextConverter.TEXT_LAYOUT_FORMAT)}"/> </s:Application>