Reviewed by Sam Weinig

        https://bugs.webkit.org/show_bug.cgi?id=21952
        
        Address an outstanding FIXME by removing unused SPI

        * History/WebHistory.mm:
        (-[WebHistory _addItemForURL:title:]): Fold addItem: into this method

        * History/WebHistoryPrivate.h: Removed unused/unneccessary SPI



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@37975 268f45cc-cd09-0410-ab3c-d52691b4dbfc