Bug 7235 [Contributions] Need dispose() for action delegates
bundles/org.eclipse.jface/src/org/eclipse/jface/action/IContributionItem.java
*  <code>false</code> for normal items
 */
public boolean isDynamic();
/**
 * Returns whether this contribution item is a group marker.
 * This information is used when adding items to a group.
 *
 * @return <code>true</code> if this item is a group marker, and
 *  <code>false</code> for normal items
 *
 * @see GroupMarker
 * @see IContributionManager#appendToGroup
 * @see IContributionManager#prependToGroup
 */
public boolean isGroupMarker();
/**
 * Returns whether this contribution item is a separator.
 * This information is used to enable hiding of unnecessary separators.
 *
 * @return <code>true</code> if this item is a separator, and
 *  <code>false</code> for normal items
 * @see Separator
 */
public boolean isSeparator();
/**
 * Returns whether this contribution item is visibile within its manager.
 *
 * @return <code>true</code> if this item is visible, and
 *  <code>false</code> otherwise
 */