Reviewed by Oliver.

    Reviewed by Oliver.

        - http://bugs.webkit.org/show_bug.cgi?id=16684
          eliminate debugger overhead from function body execution

        Speeds SunSpider up 1.003x. That's a small amount, but measurable.

        * JavaScriptCore.exp: Updated.
        * kjs/Parser.h:
        (KJS::Parser::parse): Create the node with a static member function named create() instead
        of using new explicitly.

        * kjs/grammar.y: Changed calls to new FunctionBodyNode to use FunctionBodyNode::create().

        * kjs/nodes.cpp:
        (KJS::ProgramNode::create): Added. Calls new.
        (KJS::EvalNode::create): Ditto.
        (KJS::FunctionBodyNode::create): Ditto, but creates FunctionBodyNodeWithDebuggerHooks
        when a debugger is present.
        (KJS::FunctionBodyNode::execute): Removed debugger hooks.
        (KJS::FunctionBodyNodeWithDebuggerHooks::FunctionBodyNodeWithDebuggerHooks): Added.
        (KJS::FunctionBodyNodeWithDebuggerHooks::execute): Calls the debugger, then the code,
        then the debugger again.

        * kjs/nodes.h: Added create functions, made the constructors private and protected.

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@29059 268f45cc-cd09-0410-ab3c-d52691b4dbfc