https://bugs.webkit.org/show_bug.cgi?id=19180
        speed up SunSpider by optimizing immediate number cases

        2% speedup overall, maximum 10% on controlflow-recursive and bitops-3bit-bits-in-byte,
        but a 4% regression on bitops-bits-in-byte and bitops-bitwise-and.

        * kjs/JSImmediate.h:
        (KJS::JSImmediate::canDoFastAdditiveOperations):
        (KJS::JSImmediate::addImmediateNumbers):
        (KJS::JSImmediate::subImmediateNumbers):
        Added fast cases that work with positive values less than 2^30.

        * VM/Machine.cpp:
        (KJS::Machine::privateExecute): Use the above operations. Also updated SunSpider frequencies
        with my results (looks like tag values have changed, not sure what caused the minor variation
        in actual frequencies).



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@34170 268f45cc-cd09-0410-ab3c-d52691b4dbfc