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/ListDialogField.java
}	
	/**
	 * Adds an element at a position.
	 */		
	public void insertElementAt(Object element, int index) {
		if (fElements.contains(element)) {
			return;
		}
		fElements.add(index, element);
		if (fTable != null) {
			fTable.add(element);
		}
		
		dialogFieldChanged();
	}	
	/**
	 * Adds an element at a position.
	 */	
	public void removeAllElements() {
		if (fElements.size() > 0) {
			fElements.clear();
			if (fTable != null) {
				fTable.refresh();
			}
			dialogFieldChanged();
		}
	}
		
	/**
	 * Removes an element from the list.