Bug 280846 [UI][CSS] Null styling engine required in main context for tests to run
bundles/org.eclipse.e4.ui.workbench/src/org/eclipse/e4/workbench/ui/internal/Workbench.java
IExtensionRegistry registry, IExceptionHandler exceptionHandler,
			IContributionFactory contributionFactory) {
		final IEclipseContext mainContext = EclipseContextFactory.create(applicationContext,
				UISchedulerStrategy.getInstance());
		mainContext.set(Logger.class.getName(), ContextInjectionFactory.inject(
				new WorkbenchLogger(), mainContext));
		mainContext.set(IContextConstants.DEBUG_STRING, "globalContext"); 
		
		if (contributionFactory != null) {
			mainContext.set(IContributionFactory.class.getName(), contributionFactory);
		}
		mainContext.set(CommandManager.class.getName(), new CommandManager());
		mainContext.set(ContextManager.class.getName(), new ContextManager());
		mainContext.set(ECommandService.class.getName(), new ContextCommandService(mainContext));
		mainContext.set(IServiceConstants.ACTIVE_CONTEXTS, new ActiveContextsFunction());
		mainContext.set(IServiceConstants.ACTIVE_PART, new ActivePartLookupFunction());
		mainContext.runAndTrack(new Runnable() {
			public void run() {
				Object o = mainContext.get(IServiceConstants.ACTIVE_PART);
				if (o instanceof MContributedPart<?>) {
					mainContext.set(IServiceConstants.ACTIVE_PART_ID, ((MContributedPart<?>) o)
							.getId());
				}
			}
		}, IServiceConstants.ACTIVE_PART_ID);
		
		
		IConfigurationElement[] contributions = registry
				.getConfigurationElementsFor("org.eclipse.e4.services"); 
		for (IConfigurationElement contribution : contributions) {