Bug 173902 remove EXPERIMENTAL markings from 3.3 IDE Undo API
Need to remove the EXPERIMENTAL javadoc from the new API I introduced in 3.3. See org.eclipse.ui.ide.undo org.eclipse.jface.fieldassist
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/undo/AbstractWorkspaceOperation.java
* 
	 */
	protected void markInvalid() {
		isValid = false;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * This implementation checks a validity flag.
	 * 
	 * @see org.eclipse.core.commands.operations.IUndoableOperation#canExecute()
	 */
	public boolean canExecute() {
		return isValid();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * This implementation checks a validity flag.
	 * 
	 * @see org.eclipse.core.commands.operations.IUndoableOperation#canUndo()
	 */
	public boolean canUndo() {
		return isValid();
	}
	/*
	 * (non-Javadoc)
	 * 
	 * This implementation checks a validity flag.
	 *