Bug 65315 [validateEdit] CVS-Edit: refactoring doesn't show request dialog
RC1 1. On the CVS preference page check 'Configure projects to use Watch/Edit' and 'Send a CVS edit notification to the server' and 'Always prompt' 2. Check out a CVS project and open a file in the editor 3. Rename the type -> no 'Perform Edit' request dialog is shown, although I said 'Always prompt'
org.eclipse.ltk.core.refactoring/src/org/eclipse/ltk/core/refactoring/Change.java
*        undo.initializeValidationState(new SubProgressMonitor(pm, 1));
 *        // do something with the undo object
 *     }
 *   } finally {
 *     change.dispose();
 *   }
 * </pre>
 * </p>
 * <p>
 * It is important that implementors of this abstract class provide an adequate 
 * implementation of <code>isValid</code> and that they provide an undo change
 * via the return value of the method <code>perform</code>. If no undo can be
 * provided then the perform method is allowed to return <code>null</code>. But
 * implementors should be aware that not providing an undo object for a change 
 * object that is part of a larger change tree will result in the fact that for
 * the whole change tree no undo object will be present.    
 * </p>
 * <p>
 * Clients may subclass this class.
 * </p>
 * 
 * @since 3.0
 */
public abstract class Change implements IAdaptable {
	private Change fParent;
	private boolean fIsEnabled= true;
	
	/**
	 * Constructs a new change object.
	 */