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/CommonDragAssistantDescriptor.java
private IConfigurationElement element;
	
	 CommonDragAssistantDescriptor(IConfigurationElement aConfigElement) {
		element = aConfigElement;
	}
	/**
	 * Create an instance of the {@link CommonDragAdapterAssistant} defined by
	 * this descriptor.
	 * 
	 * @return an instance of the {@link CommonDragAdapterAssistant} or
	 *         {@link SkeletonCommonDragAssistant} if a problem occurs with the
	 *         instantiation.
	 */
	public CommonDragAdapterAssistant createDragAssistant() {
		try {
			return (CommonDragAdapterAssistant) element
					.createExecutableExtension(ATT_CLASS);
		} catch (CoreException e) {
			NavigatorPlugin.logError(0, e.getMessage(), e);
		} catch (RuntimeException re) {
			NavigatorPlugin.logError(0, re.getMessage(), re);
		}
		return SkeletonCommonDragAssistant.INSTANCE;
	}
}