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/NavigatorContentExtension.java
return null;
	}
	/**
	 * @return Returns the contentProviderInitializationFailed.
	 */
	public boolean hasContentProviderInitializationFailed() {
		return contentProviderInitializationFailed;
	}
	/**
	 * @return Returns the labelProviderInitializationFailed.
	 */
	public boolean hasLabelProviderInitializationFailed() {
		return labelProviderInitializationFailed;
	}
	/**
	 * 
	 * @return True if the loading of the content provider has failed.
	 */
	public boolean hasLoadingFailed() {
		return contentProviderInitializationFailed;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see
	 * org.eclipse.ui.internal.navigator.extensions.INavigatorContentExtension
	 * #isLoaded()
	 */
	public boolean isLoaded() {
		return contentProvider != null;