Reviewed by Darin Adler.

        Removed some reliance on callFame[CodeBlock] by storing CodeBlock in a
        local variable in the Interpreter.
        https://bugs.webkit.org/show_bug.cgi?id=39447

        Small speedup on SunSpider in Interpreter mode.

        * interpreter/Interpreter.cpp:
        (JSC::Interpreter::privateExecute):
        * jsc.cpp:
        * wtf/Platform.h:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@59863 268f45cc-cd09-0410-ab3c-d52691b4dbfc