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
* Typically this method is implemented in one of the following ways: 
	 * <ul>
	 *   <li>the change hooks up a listener on some delta notification mechanism
	 *       and marks itself as invalid if it receives a certain delta. Is this 
	 *       the case the implementor must take care of unhooking the listener
	 *       in <code>dispose</code>.</li>
	 *   <li>the change remembers some information allowing to decide if a change
	 *       object is still valid when <code>isValid</code> is called.</li>
	 * </ul>
	 * <p>
	 * For example, a change object that manipulates the content of an <code>IFile</code>
	 * could either listen to resource changes and detect that the file got changed or
	 * it could remember some content stamp and compare it with the actual content stamp 
	 * when <code>isValid</code> is called.
	 * </p>
	 * 
	 * @param pm a progress monitor
	 */
	public abstract void initializeValidationData(IProgressMonitor pm);
	
	/**
	 * Verifies that this change object is still valid and can be executed by calling 
	 * <code>perform</code>. If a refactoring status  with a severity of {@link 
	 * RefactoringStatus#FATAL} is returned then the change has to be treated as invalid 
	 * and can no longer be executed. Performing such a change produces an unspecified 
	 * result and will very likely throw an exception.
	 * <p>
	 * This method is also called by the {@link IUndoManager UndoManager} to decide if
	 * an undo or redo change is still valid and therefore can be executed.
	 * </p>