I get script error when I undo replace text

[Zoltan Koszegi]

I tried this with DEMO page with IE9.
STR:
Replace anything e.g. a word at the and of any paragraph. After dismissing the replace dialog press undo.

RESULT:
Webpage Error says:
Line: 345
Error: DOM Exception: INDEX_SIZE_ERR (1)

NOTE: Easy way: Select a word that contains an end of a paragraph, then press replace tool and type anything to the "Replace with", then press "Replace", then Cancel for the dialog. Press undo.

[Olek Nowodziński]

Duplicate of #10301.