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/NavigatorContentServiceContentProvider.java
if (!ext.isLoaded() && !enforceHasChildren)
				return true;
			NavigatorContentExtension[] overridingExtensions;
			if (!isOverridingExtensionInSet(ext.getDescriptor(), enabledExtensions)) {
				try {
					SafeDelegateTreeContentProvider cp = ext.internalGetContentProvider();
					suggestedHasChildren |= callNormalHasChildren(anElementOrPath, anElement, cp);
					overridingExtensions = ext.getOverridingExtensionsForTriggerPoint(anElement);
					if (overridingExtensions.length > 0) {
						suggestedHasChildren = pipelineHasChildren(anElementOrPath, anElement, overridingExtensions,
								suggestedHasChildren);
					}
					if (suggestedHasChildren)
						return true;
				} catch (Throwable e) {
					NavigatorPlugin.logError(0, NLS.bind(
							CommonNavigatorMessages.Exception_Invoking_Extension, new Object[] {
									ext.getDescriptor().getId(), anElementOrPath }), e);
				}
			}
		}
		return suggestedHasChildren;
	}
	public boolean hasChildren(TreePath path) {
		return hasChildren((Object)path);
	}
	private boolean callNormalHasChildren(Object anElementOrPath, Object anElement, SafeDelegateTreeContentProvider cp) {
		if (cp.isTreePath() && anElementOrPath instanceof TreePath) {
			ITreePathContentProvider tpcp = (ITreePathContentProvider) cp;
			return tpcp.hasChildren((TreePath) anElementOrPath);