Bug 137073 [Preferences] Encoding field editor never fires value change events
The class AbstractEncodingFieldEditor never fires VALUE property change events unless the validaty of the value has also changed. I will attach a patch that corrects the problem.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/dialogs/AbstractEncodingFieldEditor.java
*/
	protected AbstractEncodingFieldEditor() {
		super();
	}
	/**
	 * Creates a new encoding field editor with the given preference name, label
	 * and parent.
	 * 
	 * @param name
	 *            the name of the preference this field editor works on
	 * @param labelText
	 *            the label text of the field editor
	 * @param parent
	 *            the parent of the field editor's control
	 */
	protected AbstractEncodingFieldEditor(String name, String labelText,
			Composite parent) {
		super(name, labelText, parent);
	}
	/**
	 * Creates a new encoding field editor with the given preference name, label
	 * and parent.
	 * 
	 * @param name
	 *            the name of the preference this field editor works on
	 * @param labelText
	 *            the label text of the field editor
	 * @param groupTitle
	 *            the title for the field editor's control. If groupTitle is 
	 *            <code>null</code> the control will be unlabelled