Bug 315281 update copyrights for 3.6
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/dnd/CommonDropDescriptorManager.java
*            The drop target of the operation
	 * @param aContentService
	 *            The associated content service to filter results by.
	 * @return An array of drop descriptors that can handle the given drop
	 *         target and are <i>visible</i> and <i>active</i> for the given
	 *         service and <i>enabled</i> for the given drop target..
	 */
	public CommonDropAdapterDescriptor[] findCommonDropAdapterAssistants(Object aDropTarget, INavigatorContentService aContentService) {
		Set foundDescriptors = new LinkedHashSet();
		for (Iterator iter = dropDescriptors.keySet().iterator(); iter
				.hasNext();) {
			INavigatorContentDescriptor contentDescriptor = (INavigatorContentDescriptor) iter
					.next();
			if (aContentService.isVisible(contentDescriptor.getId())
					&& aContentService.isActive(contentDescriptor.getId())) {
				List dropDescriptors = getDropDescriptors(contentDescriptor);
				for (Iterator iterator = dropDescriptors.iterator(); iterator
						.hasNext();) {
					CommonDropAdapterDescriptor dropDescriptor = (CommonDropAdapterDescriptor) iterator
							.next();
					if (dropDescriptor.isDropElementSupported(aDropTarget)) {
						foundDescriptors.add(dropDescriptor);
					}
				}
			}
		}
		if (foundDescriptors.isEmpty()) {
			return NO_DESCRIPTORS;
		}
		return (CommonDropAdapterDescriptor[]) foundDescriptors