Fix animation errors with radio buttons and checkboxes on Windows.

The QWindowsVistaStyle used the animation state of the control's
style object. Since this is the QWebView for controls used in
QtWebKit, this leads to unpredictable painting behavior.

Task-number: QTBUG-30072
Change-Id: I1ba572bfbf56745b8e85fd631a596c43aa2ba25a
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@digia.com>