Bug 46351 Call Hierarchy must not implement IViewSite [call hierarchy]
I20031105 The call hierarchy component implements IViewSite which is not allowed. There seems to be no reason for doing so: the CallHierarchyViewPart should directly set the selection provider to its site.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/callhierarchy/SelectionProviderMediator.java
doSelectionChanged(event);
		}
		
	    /*
	     * @see FocusListener#focusGained
	     */
	    public void focusGained(FocusEvent e) {    	
	    	doFocusChanged(e.widget);
	    }
	
	    /*
	     * @see FocusListener#focusLost
	     */
	    public void focusLost(FocusEvent e) {
	    	
	    	
	    }
	}
	
	private Viewer[] fViewers;
	private InternalListener fListener;
	
	private Viewer fViewerInFocus;
	private ListenerList fSelectionChangedListeners;
	
	/**
	 * @param All viewers that can provide a selection
	 */
	public SelectionProviderMediator(Viewer[] viewers) {
		Assert.isNotNull(viewers);