The test-case attached has instructions. The short version is that there is a font-tag inside a blockquote. Selecting from the beginning of the font-tag to the end of the contentEditable region and hitting delete gets rid of the blockquote tag and not the font tag. It should either get rid of both or keep both. I think the right thing is to keep both. This is what IE does. It's also what MS Word does in my brief testing.
Created attachment 21866 [details] reduced test case
Created attachment 139753 [details] Adds a test This bug appears to have been fixed. Let's just add a test.
Comment on attachment 139753 [details] Adds a test View in context: https://bugs.webkit.org/attachment.cgi?id=139753&action=review > LayoutTests/editing/execCommand/delete-line-and-insert-text-in-font-inside-blockquote-expected.txt:3 > +There should be exactly one blockquote and you should see "hello world" below: WTF... I swear I've replaced by a space.
Created attachment 139754 [details] Did s/ / /
Created attachment 139866 [details] Right patch
Comment on attachment 139866 [details] Right patch Looks good to me.
Comment on attachment 139866 [details] Right patch Clearing flags on attachment: 139866 Committed r115884: <http://trac.webkit.org/changeset/115884>
All reviewed patches have been landed. Closing bug.