and this is code from skin

<s:RichEditableText id="textDisplay"
                            multiline="{hostComponent.multiline}"
                            lineBreak="toFit"
                            color="{hostComponent.textColor}"
                            fontFamily="{hostComponent.fontFamily}"
                            fontSize="{hostComponent.fontSize}"
                            focusedTextSelectionColor="0xddf1f8"
                            left="6" right="1" top="4" bottom="1"
                            kerning="off"
                            heightInLines="{hostComponent.lines}"
                            >
        </s:RichEditableText>

ok, im trying to fix this now, so that's why I'm replying later

First test and found first problem. When I have strings with \n inside and do not set width and height (need to set both to fix problem) in Profiler you can see infinity loop which try to find out correct size (dont know if this is problem of layout component itself, or together with RichEditableText, but for text without \n it works correctly

Here is example code. You can try to change textData in init() function and run in in profiler (SDK 4.0.14403). To fix problem set width for all 3 instances of RichEditableText.

<?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/halo"
               minWidth="1024" minHeight="768"
               applicationComplete="init()"
               xmlns:components="com.bbdo.totalWorkPlanner.app.view.components.*">
    <fx:Declarations>
        <!-- Place non-visual elements (e.g., services, value objects) here -->
    </fx:Declarations>
   
    <s:HGroup>
        <s:BorderContainer>
            <s:RichEditableText id="textInput"
                                multiline="true"
                                lineBreak="toFit"
                                height="200"
                                color="0xaaaaa"
                                left="6" right="1" top="4" bottom="1"
                                kerning="off"
                                heightInLines="10"
                                >
            </s:RichEditableText>
        </s:BorderContainer>
        <s:Button label="update" click="update()"/>
        <s:VGroup>
            <s:BorderContainer>
                <s:RichEditableText id="textDisplay1"
                                    text="{textData}"
                                    height="200"
                                    multiline="true"
                                    lineBreak="toFit"
                                    color="0xaaaaa"
                                    left="6" right="1" top="4" bottom="1"
                                    kerning="off"
                                    heightInLines="10"
                                    >
                </s:RichEditableText>
            </s:BorderContainer>   
            <s:BorderContainer>
                <s:RichEditableText id="textDisplay2"
                                    text="{textData}"
                                    height="30"
                                    multiline="false"
                                    lineBreak="toFit"
                                    color="0xaaaaa"
                                    left="6" right="1" top="4" bottom="1"
                                    kerning="off"
                                    heightInLines="1"
                                    >
                </s:RichEditableText>
            </s:BorderContainer>
        </s:VGroup>
    </s:HGroup>
   
    <fx:Script>
        <![CDATA[
            [Bindable]
            public var textData:String;
           
            private function init():void
            {
                //textData = "Fearful criminals.    \n\nAlso theme-based super-villians.  Or super-villians too interested in villiany to establish a theme (i.e. slackers).  \n\nBasically any bad-guys that can be defeated by being beaten up by a guy who wears his underwear on the outside of his pants and talks in a growly voice.";
                textData = "test data.";//    \n\ntest  \n\ndata";
            }
            private function update():void
            {
                textData = textInput.text
                trace(textData);
            }
        ]]>
    </fx:Script>
   
</s:Application>

But this was not my main problem. I just found this when trying to found problem itself.

Now there is infinite calling of SizesAndLimit (for VerticalLayout and HorizontalLayout) and LayoutElementFlexChildInfo (for VerticalLayout)

in my app, there are command about creating TextFlow (or something similar) I will provide information later today