Bug 285529 [CommonNavigator] Incorrect pipeline logic for interceptXxx methods
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/extensions/NavigatorContentExtension.java
overridingDescriptor = (NavigatorContentDescriptor) contentDescriptorsItr
					.next();
			if (contentService.isActive(overridingDescriptor.getId())
					&& contentService.isVisible(overridingDescriptor.getId())
					&& overridingDescriptor.isPossibleChild(anElement)) {
				overridingExtensions.add(contentService
						.getExtension(overridingDescriptor));
			}
		}
		if (overridingExtensions.size() == 0) {
			return NO_EXTENSIONS;
		}
		if (Policy.DEBUG_EXTENSION_SETUP) {
			System.out.println(this +  " overriding: "+
					"(poss child: " + anElement + "): " + overridingExtensions); 
		}
		return (NavigatorContentExtension[]) overridingExtensions
				.toArray(new NavigatorContentExtension[overridingExtensions
						.size()]);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see java.lang.Object#toString()
	 */
	public String toString() {
		return descriptor.toString() + " Instance"; 
	}
}