Bug 84353 [typing] Hippie completion fills undo stack
I20050202-0800 Toggling through the lists adds each item to the undo stack and hence Undo (Ctrl+Z) undoes each by each.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/javaeditor/JavaMoveLinesAction.java
if (!validateEditorInputState())
			return;
		ISourceViewer viewer= fSharedState.fEditor.getViewer();
		if (viewer == null)
			return;
		IDocument document= viewer.getDocument();
		if (document == null)
			return;
		StyledText widget= viewer.getTextWidget();
		if (widget == null)
			return;
		
		Point p= viewer.getSelectedRange();
		if (p == null)
			return;
		ITextSelection sel= new TextSelection(document, p.x, p.y);
		ITextSelection skippedLine= getSkippedLine(document, sel);
		if (skippedLine == null)
			return;
		try {
			ITextSelection movingArea= getMovingSelection(document, sel, viewer);
			
			
			if (!containedByVisibleRegion(movingArea, viewer) || !containedByVisibleRegion(skippedLine, viewer))
				return;
			
			String moving= movingArea.getText();
			String skipped= skippedLine.getText();
			if (moving == null || skipped == null)
				return;