CssClassUiEvent
Emitted for subscribers to provide a cssClass hint (equivalent to the cssClass() supporting method or the DomainObjectLayout#cssClass() element).
The class has a number of responsibilities:
- 
capture the target object being interacted with
 - 
capture the CSS class, if any, as specified to one of the subscribers
 
The class itself is instantiated automatically by the framework.
API
CssClassUiEvent.java
class CssClassUiEvent<S> {
  CssClassUiEvent()     (1)
  CssClassUiEvent(S source)
  void setCssClass(String cssClass)     (2)
}
| 1 | CssClassUiEvent()
 If used then the framework will set state via (non-API) setters.  | 
| 2 | setCssClass(String)
 For subscribers to call to provide a CSS class for this object.  |