Bug 80429 [Preferences] [Dialogs] FieldEditors should relax requirements to support DialogPages
bundles/org.eclipse.jface/src/org/eclipse/jface/preference/FieldEditorPreferencePage.java
return true;
    }
    /**
     * The field editor preference page implementation of this <code>IPreferencePage</code>
     * (and <code>IPropertyChangeListener</code>) method intercepts <code>IS_VALID</code> 
     * events but passes other events on to its superclass.
     */
    public void propertyChange(PropertyChangeEvent event) {
        if (event.getProperty().equals(FieldEditor.IS_VALID)) {
            boolean newValue = ((Boolean) event.getNewValue()).booleanValue();
            
            
            if (newValue) {
                checkState();
            } else {
                invalidFieldEditor = (FieldEditor) event.getSource();
                setValid(newValue);
            }
        }
    }
    /* (non-Javadoc)
     * Method declared on IDialog.
     */
    public void setVisible(boolean visible) {
        super.setVisible(visible);
        if (visible && invalidFieldEditor != null) {
            invalidFieldEditor.setFocus();
        }
    }
}