Bug 64855 QuickMenuAction leaks the context menus
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/actions/QuickMenuAction.java
* 
	 * @param table the table widget that has the focus
	 * 
	 * @return a widget relative position of the menu to pop up or
	 *  <code>null</code> if now position inside the widget can
	 *  be computed
	 */
	protected Point computeMenuLocation(Table table) {
		TableItem[] items= table.getSelection();
		Rectangle clientArea= table.getClientArea();
		switch (items.length) {
			case 0: {
				return null;
			} case 1: {
				Rectangle bounds= items[0].getBounds(0);
				Rectangle iBounds= items[0].getImageBounds(0);
				Rectangle intersect= clientArea.intersection(bounds);
				if (intersect != null && intersect.height == bounds.height) {
					return new Point(
						Math.max(0, bounds.x + iBounds.width + getAvarageCharWith(table) * CHAR_INDENT), 
						bounds.y + bounds.height);
				} else {
					return null;
				}
			} default: {
				Rectangle[] rectangles= new Rectangle[items.length];
				for (int i= 0; i < rectangles.length; i++) {
					rectangles[i]= items[i].getBounds(0);
				}
				Rectangle iBounds= items[0].getImageBounds(0);