Reimplement QVariantAnimation::updateState() properly

Reimplement QVariantAnimation::updateState() properly

The updateState() takes 2 arguments, not 1.

tests/benchmarks/gui/animation/qanimation/dummyanimation.h:54: warning:
'DummyAnimation::updateState' hides overloaded virtual function
[-Woverloaded-virtual]
    void updateState(State state);
         ^
src/corelib/animation/qvariantanimation.h:106: hidden overloaded virtual
function 'QVariantAnimation::updateState' declared here
    void updateState(QAbstractAnimation::State newState, QAbstractAnimation::State oldState);
         ^

Change-Id: Ieb2e4e0b1f017c51c4fed5bdb874ba30cb056916
Reviewed-by: Robin Burchell <robin+qt@viroteck.net>
Reviewed-by: Joerg Bornemann <joerg.bornemann@nokia.com>