Reviewed by Darin.

    Reviewed by Darin.

        - avoid creating and then breaking circular lists in the parser, instead track head and tail pointers at parse time
        http://bugs.webkit.org/show_bug.cgi?id=15748

        Not a significant speedup or slowdown on SunSpider.

        * kjs/Parser.cpp:
        (KJS::clearNewNodes):
        * kjs/Parser.h:
        * kjs/grammar.y:
        * kjs/nodes.cpp:
        (KJS::BlockNode::BlockNode):
        (KJS::CaseBlockNode::CaseBlockNode):
        (KJS::FunctionBodyNode::FunctionBodyNode):
        (KJS::SourceElementsNode::SourceElementsNode):
        (KJS::ProgramNode::ProgramNode):
        * kjs/nodes.h:
        (KJS::ElementNode::):
        (KJS::ArrayNode::):
        (KJS::PropertyListNode::):
        (KJS::ObjectLiteralNode::):
        (KJS::ArgumentListNode::):
        (KJS::ArgumentsNode::):
        (KJS::VarDeclListNode::):
        (KJS::VarStatementNode::):
        (KJS::ForNode::):
        (KJS::ParameterNode::):
        (KJS::FuncExprNode::):
        (KJS::FuncDeclNode::):
        (KJS::SourceElementsNode::):
        (KJS::CaseClauseNode::):
        (KJS::ClauseListNode::):

git-svn-id: https://svn.webkit.org/repository/webkit/trunk@27215 268f45cc-cd09-0410-ab3c-d52691b4dbfc