Bug 139986 [CommonNavigator] Convert catch(Error/Throwable) to SafeRunner
In several places the CN framework uses catch(Error/Throwable) to ensure that code does not bring the framework down. Change these to use SafeRunner.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/wizards/CommonWizardDescriptorManager.java
return (String[]) descriptorIds.toArray(wizardIds); 
	}
	
	/**
	 * 
	 * Returns all wizard descriptor(s) which enable for the given element.
	 * 
	 * @param anElement
	 *            the element to return the best content descriptor for
	 * @param aType
	 *            The type of wizards to locate (e.g. 'new', 'import', or
	 *            'export' etc).
	 * @param aContentService 
	 * 			 The content service to use when deciding visibility.   
	 * @return The set of commonWizard descriptors for the element
	 */
	public CommonWizardDescriptor[] getEnabledCommonWizardDescriptors(Object anElement,
			String aType, INavigatorContentService aContentService) {
		Set commonDescriptors = (Set) commonWizardDescriptors.get(aType);
		if (commonDescriptors == null) {
			return NO_DESCRIPTORS;
		}
		
		List descriptors = new ArrayList();
		for (Iterator commonWizardDescriptorsItr = commonDescriptors.iterator(); commonWizardDescriptorsItr
				.hasNext();) {
			CommonWizardDescriptor descriptor = (CommonWizardDescriptor) commonWizardDescriptorsItr
					.next();
			if (isVisible(aContentService, descriptor)
					&& descriptor.isEnabledFor(anElement)) {