Bug 299340 [CommonNavigator] Enable new CNF tests
Enable the contributed CNF tests, make minor test improvements.
tests/org.eclipse.ui.tests.navigator/src/org/eclipse/ui/tests/navigator/M12Tests.java
newFolder1.delete(true, new NullProgressMonitor());
		folder1Item = _findChild(NEW_FOLDER_1, rootItems[_p1Ind].getItems());
		assertNull(
				"[bug 285529] M1 interceptRemove method should have been called",
				folder1Item);
	}
	/**
	 * Verifies that interceptUpdate or interceptRefresh is called when a child
	 * is replaced. Fails in Galileo due to faulty implementation of
	 * NavigatorContentExtension.getOverridingExtensionsForPossibleChild(...)
	 * which doesn't consider M1 because the M1 content provider doesn't have
	 * IResource as possible children. M1 replaces IResources with M1Resources,
	 * its interceptRefresh method should be called when
	 * viewer.refresh(IResource) is called.
	 * 
	 * @throws CoreException
	 */
	
	public void testInterceptRefreshOnChildTypeChange() throws CoreException {
		_initContent();
		final IFile file2 = _p2.getFile("file2.txt");
		IWorkspaceRunnable runnable = new IWorkspaceRunnable() {
			public void run(IProgressMonitor monitor) throws CoreException {
				file2.delete(true, new NullProgressMonitor());
				file2.create(null, true, null);
			}
		};
		M1ContentProvider.resetCounters();
		M2ContentProvider.resetCounters();
		ResourcesPlugin.getWorkspace().run(runnable, new NullProgressMonitor());