Bug 181061 [Viewers] JFace viewers performance issues in 3.3
A number of the JFace performance tests are red since I20060926-0800.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTableViewer.java
* Returns the number of items contained in the receiver.
	 * 
	 * @return the number of items
	 * 
	 * @since 3.3
	 */
	protected abstract int doGetItemCount();
	/**
	 * Sets the number of items contained in the receiver.
	 * 
	 * @param count
	 *            the number of items
	 * 
	 * @since 3.3
	 */
	protected abstract void doSetItemCount(int count);
	/**
	 * Returns a (possibly empty) array of TableItems which are the items in the
	 * receiver.
	 * 
	 * @return the items in the receiver
	 * 
	 * @since 3.3
	 */
	protected abstract Item[] doGetItems();
	/**
	 * Returns the column at the given, zero-relative index in the receiver.
	 * Throws an exception if the index is out of range. Columns are returned in
	 * the order that they were created. If no TableColumns were created by the
	 * programmer, this method will throw ERROR_INVALID_RANGE despite the fact