The following Chromium bug documents the issue and has step-by-step repro steps.
I prepared a patch for Blink that is in the process of getting committed. This bug is for tracking my progress on porting the patch to WebKit.
I filed the bug under "HTML DOM", but the fix will go under WebCore/editing.
Created attachment 216209 [details]
Chris, I think this would help HTML5 compliance, so I'm cc-ing you on it.
Chromium already implements this behavior, as well as Firefox and IE10.
Comment on attachment 216209 [details]
Clearing flags on attachment: 216209
Committed r159326: <http://trac.webkit.org/changeset/159326>
All reviewed patches have been landed. Closing bug.
Thank you very much, Darin!