private JComponent buildCenterComponent() {
		JComponent centerComponent = scroller;
		MarginProvider resizeableMarginProvider = getResizeableMarginProvider();
		if (resizeableMarginProvider != null) {
			if (splitPane != null) {
				splitPaneDividerLocation = splitPane.getDividerLocation();
			}
			JPanel resizeablePanel = new JPanel(new ScrollpanelResizeablePanelLayout(scroller));
			resizeablePanel.setBackground(Colors.BACKGROUND);
			resizeablePanel.add(resizeableMarginProvider.getComponent());
			splitPane = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, resizeablePanel, scroller);
			splitPane.setDividerSize(4);
			splitPane.setDividerLocation(splitPaneDividerLocation);
			splitPane.setContinuousLayout(true);
			splitPane.setBorder(null);
			centerComponent = splitPane;
		}
		if (headerPanel != null) {
			headerPanel.setViewComponent(centerComponent);
			centerComponent = headerPanel;
		}

		return centerComponent;
	}
Adds the MarginProvider to this panel

@param provider the MarginProvider that will provide components to display in this panel's
           left margin area.
Ghidra/Features/Base/src/main/java/ghidra/app/util/viewer/listingpanel/ListingPanel.java