Reviewed by Chris

    Reviewed by Chris

        Fix for this bug:

        <rdar://problem/4026906> Paste of HTML table content can break table structure

        * khtml/editing/htmlediting.cpp:
        (khtml::ReplacementFragment::pruneEmptyNodes): Call new isProbablyTableStructureNode() function to prevent
        removal of empty table structure nodes.
        (khtml::ReplacementFragment::removeUnrenderedNodesUsingTestRendering): Ditto.
        (khtml::isProbablyTableStructureNode): New helper function.
        * khtml/editing/htmlediting.h: Declare new helper.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@8716 268f45cc-cd09-0410-ab3c-d52691b4dbfc