Reviewed by darin.

        Add simple type inferencing to the parser, and create custom
        AddNode and LessNode subclasses based on inferred types.
        http://bugs.webkit.org/show_bug.cgi?id=15884

        SunSpider claims this is at least a 0.5% speedup.

        * JavaScriptCore.exp:
        * kjs/grammar.y:
        * kjs/internal.cpp:
        (KJS::NumberImp::getPrimitiveNumber):
        (KJS::GetterSetterImp::getPrimitiveNumber):
        * kjs/internal.h:
        * kjs/lexer.cpp:
        (KJS::Lexer::lex):
        * kjs/nodes.cpp:
        (KJS::Node::Node):
        (KJS::StringNode::evaluate):
        (KJS::StringNode::evaluateToNumber):
        (KJS::StringNode::evaluateToBoolean):
        (KJS::RegExpNode::evaluate):
        (KJS::UnaryPlusNode::optimizeVariableAccess):
        (KJS::AddNode::evaluate):
        (KJS::AddNode::evaluateToNumber):
        (KJS::AddNumbersNode::inlineEvaluateToNumber):
        (KJS::AddNumbersNode::evaluate):
        (KJS::AddNumbersNode::evaluateToNumber):
        (KJS::AddStringsNode::evaluate):
        (KJS::AddStringLeftNode::evaluate):
        (KJS::AddStringRightNode::evaluate):
        (KJS::lessThan):
        (KJS::lessThanEq):
        (KJS::LessNumbersNode::evaluate):
        (KJS::LessStringsNode::evaluate):
        * kjs/nodes.h:
        (KJS::ExpressionNode::):
        (KJS::RegExpNode::):
        (KJS::RegExpNode::precedence):
        (KJS::TypeOfResolveNode::):
        (KJS::LocalVarTypeOfNode::):
        (KJS::UnaryPlusNode::):
        (KJS::UnaryPlusNode::precedence):
        (KJS::AddNode::):
        (KJS::AddNode::precedence):
        (KJS::AddNumbersNode::):
        (KJS::AddStringLeftNode::):
        (KJS::AddStringRightNode::):
        (KJS::AddStringsNode::):
        (KJS::LessNode::):
        (KJS::LessNode::precedence):
        (KJS::LessNumbersNode::):
        (KJS::LessStringsNode::):
        * kjs/nodes2string.cpp:
        (KJS::StringNode::streamTo):
        * kjs/object.cpp:
        * kjs/object.h:
        * kjs/value.h:
        (KJS::JSValue::getPrimitiveNumber):


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@27695 268f45cc-cd09-0410-ab3c-d52691b4dbfc