Bug 299208 [CommonNavigator] More helpful error message when an invalid suppressedExtensionId is referenced
The current error message does not show the if of the NCE that had the bad reference.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/extensions/NavigatorContentDescriptorManager.java
private NavigatorContentDescriptorManager() {
		new NavigatorContentDescriptorRegistry().readRegistry();
	}
	/**
	 * 
	 * @return Returns all content descriptor(s).
	 */
	public NavigatorContentDescriptor[] getAllContentDescriptors() {
		NavigatorContentDescriptor[] finalDescriptors = new NavigatorContentDescriptor[allDescriptors
				.size()];
		finalDescriptors = (NavigatorContentDescriptor[]) allDescriptors.values().toArray(finalDescriptors);
		Arrays.sort(finalDescriptors, ExtensionPriorityComparator.INSTANCE);
		return finalDescriptors;
	}
	/**
	 * 
	 * @return Returns all content descriptors that provide saveables.
	 */
	public NavigatorContentDescriptor[] getContentDescriptorsWithSaveables() {
		NavigatorContentDescriptor[] finalDescriptors = new NavigatorContentDescriptor[saveablesProviderDescriptors
				.size()];
		saveablesProviderDescriptors.toArray(finalDescriptors);
		Arrays.sort(finalDescriptors, ExtensionPriorityComparator.INSTANCE);
		return finalDescriptors;
	}
	/**
	 * 
	 * Returns all content descriptor(s) which enable for the given element.
	 * 
	 * @param anElement