Bug 158778 [Viewers] request for remove(parent, index) API on tree viewer
3.3 It would be helpful to have a 'remove(Object parent, int index)' method on the tree viewer to complement that 'replace(...)' and 'setChildCount(...)' APIs. The debug platform requires such a method to implement filtering in virtual tree views. Rather than performing a 'replace/remove' based on elements, the content provider can make one atomic call to remove an element at a specific index.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
/**
	 * This viewer's tree editor.
	 */
	private TreeEditor treeEditor;
	/**
	 * Flag for whether the tree has been disposed of.
	 */
	private boolean treeIsDisposed = false;
	/**
	 * Creates a tree viewer on a newly-created tree control under the given
	 * parent. The tree control is created using the SWT style bits
	 * <code>MULTI, H_SCROLL, V_SCROLL,</code> and <code>BORDER</code>. The
	 * viewer has no input, no content provider, a default label provider, no
	 * sorter, and no filters.
	 * 
	 * @param parent
	 *            the parent control
	 */
	public TreeViewer(Composite parent) {
		this(parent, SWT.MULTI | SWT.H_SCROLL | SWT.V_SCROLL | SWT.BORDER);
	}
	/**
	 * Creates a tree viewer on a newly-created tree control under the given
	 * parent. The tree control is created using the given SWT style bits. The
	 * viewer has no input, no content provider, a default label provider, no
	 * sorter, and no filters.
	 * 
	 * @param parent
	 *            the parent control
	 * @param style