RichEditabletext problem drawing html image with no dimension

Steps to reproduce:
1. Create a custom List that display RichEditabletext control when list item selected
2. Send in some html string that have images tag that have no width and height to the RichEditabletext control
3. Selected one of the list item.

Actual Results:
The RichEditabletext will render over item that's below it. The measurement of the RichEditabletext control seems to be incorrect when there is no dimension and draw some of the images over items below. Also the mouse scroll seems to be off after an item is selected. The mouse scroll distance change depends on any item selection.

Expected Results:
All item and images render correctly. The mouse scroll work consistently independent of any selected item.

Workaround (if any):
None