Reviewed by Hyatt.

    Reviewed by Hyatt.

        - [NSFont menuFontOfSize:], called from WebStringTruncator, was taking > 9% of the time creating a
        very large bookmarks menu, so I cached this one NSFont object.

        * Misc.subproj/WebStringTruncator.m:
        (defaultMenuFont):
        new function, caches the font used when no font is specified
        (+[WebStringTruncator centerTruncateString:toWidth:]):
        call new function

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@7929 268f45cc-cd09-0410-ab3c-d52691b4dbfc