Created Issue: IE9 HtmlEditorExtender Clearing more line content after postback [27240]

HtmlEditorExtender losing text content after postback if there were used more lines (2+) and there are missing Justify* actions in toolbar.

Steps for reproduction:

- Open your demo application (HTMLEditorExtender.aspx)
- Remove all toolbar action excluded bold, italic and udnerline:

[CODE]
<ajaxToolkit:HtmlEditorExtender ID="htmlEditorExtender2" TargetControlID="txtBox2"
runat="server" DisplaySourceTab="True" OnImageUploadComplete="ajaxFileUpload_OnUploadComplete">
<Toolbar>
<ajaxToolkit:Bold />
<ajaxToolkit:Italic />
<ajaxToolkit:Underline />
</Toolbar>
</ajaxToolkit:HtmlEditorExtender>
[/CODE]

- Write TWO lines content ie.:

"bla bla bla
gugugu"

- Click to submit content <- as you can see, content has been cleaned.

Workaround:
Add at least one justify action:

[CODE]
<Toolbar>
<ajaxToolkit:Bold />
<ajaxToolkit:Italic />
<ajaxToolkit:Underline />
<ajaxToolkit:HorizontalSeparator />
<ajaxToolkit:JustifyLeft />
</Toolbar>
[/CODE]