Restores the device context to the previous state identified by nSavedDC.
RestoreDC restores the device context by popping state information off a stack created by earlier calls to the SaveDC member function.
The stack can contain the state information for several device contexts. If the context specified by nSavedDC is not at the top of the stack, RestoreDC deletes all state information between the device context specified by nSavedDC and the top of the stack. The deleted information is lost.