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/extensions/NavigatorContentDescriptor.java
INavigatorContentDescriptor, INavigatorContentExtPtConstants {
	private static final int HASH_CODE_NOT_COMPUTED = -1;
	private String id;
	private String name;
	private IConfigurationElement configElement;
	private int priority = Priority.NORMAL_PRIORITY_VALUE;
	/**
	 * This is calculated based on the priority and appearsBeforeId when all of the descriptors
	 * are first loaded. This is what's used to sort on after that.
	 */
	private int sequenceNumber;
	
	private String appearsBeforeId;
	private Expression enablement;
	private Expression possibleChildren;
	private Expression initialActivation;
	
	private String icon;
	private boolean activeByDefault;
	private IPluginContribution contribution;
	private boolean sortOnly;
	
	private Set overridingExtensions;
	private List overridingExtensionsList;