Bug 5677 Hierarchy outline has empty space
I opened a hierarchy view on IActionDelegate. Selected a few of the subinterfaces, changed the expansion state of the tree. Then, no matter which item I selected in the top window (the hierarchy tree), the bottom window (the outline table) always had exactly four empty rows before the first item was listed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/wizards/dialogfields/CheckedListDialogField.java
private int fCheckAllButtonIndex;
	private int fUncheckAllButtonIndex;
	
	private List fCheckElements;
	public CheckedListDialogField(IListAdapter adapter, String[] customButtonLabels, ILabelProvider lprovider) {
		super(adapter, customButtonLabels, lprovider);
		fCheckElements= new ArrayList();
		
		fCheckAllButtonIndex= -1;
		fUncheckAllButtonIndex= -1;
	}
	/**
	 * Sets the index of the 'check' button in the button label array passed in the constructor.
	 * The behaviour of the button marked as the check button will then be handled internally.
	 * (enable state, button invocation behaviour)
	 */	
	public void setCheckAllButtonIndex(int checkButtonIndex) {
		Assert.isTrue(checkButtonIndex < fButtonLabels.length);
		fCheckAllButtonIndex= checkButtonIndex;
	}
	/**
	 * Sets the index of the 'uncheck' button in the button label array passed in the constructor.