Bug 56818 [PropertiesView] Clicking on Advanced Properties toggle when categories are collapsed removes the + next to the category
Clicking on Advanced Properties toggle when categories are collapsed removes the plus sign (+) next to the category and it can no longer be expanded. To reproduce: 1.)Open the Properties view. 2.)Have Show Categories turned on, and Show Advanced Properties turned off. 3.)Collapse all open categories. 4.)Click the Show Advanced Properties button. 5.)Note the plus sign goes away and the categories can no longer be expanded. You need to click the Show Advanced Properties button off to see the plus sign again.
bundles/org.eclipse.ui.views/src/org/eclipse/ui/views/properties/PropertySheetViewer.java
*/
	private void entrySelectionChanged() {
		SelectionChangedEvent changeEvent = new SelectionChangedEvent(this,
				getSelection());
		fireSelectionChanged(changeEvent);
	}
	/**
	 * Return a table tree item in the property sheet that has the same entry in
	 * its user data field as the supplied entry. Return <code>null</code> if
	 * there is no such item.
	 * 
	 * @param entry
	 *            the entry to serach for
	 */
	private TableTreeItem findItem(IPropertySheetEntry entry) {
		
		TableTreeItem[] items = tableTree.getItems();
		for (int i = 0; i < items.length; i++) {
			TableTreeItem item = items[i];
			TableTreeItem findItem = findItem(entry, item);
			if (findItem != null)
				return findItem;
		}
		return null;
	}
	/**
	 * Return a table tree item in the property sheet that has the same entry in
	 * its user data field as the supplied entry. Return <code>null</code> if
	 * there is no such item.
	 *