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/OpenLocationAction.java
return false;
        }
        for (Iterator iter = selection.iterator(); iter.hasNext();) {
            Object element = iter.next();
            if (element instanceof MethodWrapper) {
                continue;
            } else if (element instanceof CallLocation) {
                continue;
            }
            return false;
        }
        return true;
    }
    /* (non-Javadoc)
 * Method declared on SelectionDispatchAction.
 */
    public void run(IStructuredSelection selection) {
        if (!checkEnabled(selection)) {
            return;
        }
        run(selection.getFirstElement());
    }
    public void run(Object element) {
        CallHierarchyUI.openInEditor(element, getShell(), getDialogTitle());
    }
    private String getDialogTitle() {
        return CallHierarchyMessages.getString("OpenLocationAction.error.title"); 
    }
}