Reviewed by Chris

    Reviewed by Chris

        Added new createBreakElement() function that makes creating a <br> element a one-liner.
        Converted all the code that used to call the DocumentImpl, and dealt with the exceptionCode,
        over to this new helper.

        * khtml/editing/htmlediting.cpp:
        (khtml::DeleteSelectionCommand::moveNodesAfterNode): Now uses new helper function.
        (khtml::InsertLineBreakCommand::doApply): Ditto.
        (khtml::InsertParagraphSeparatorCommand::doApply): Ditto.
        (khtml::InsertParagraphSeparatorInQuotedContentCommand::doApply): Ditto.
        (khtml::ReplaceSelectionCommand::doApply): Ditto.
        (khtml::createBreakElement): New helper.
        * khtml/editing/htmlediting.h: Ditto.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8234 268f45cc-cd09-0410-ab3c-d52691b4dbfc