Bug 266146 [CSS] JUnit for: Property retrieval must check instanceof and return null
tests/org.eclipse.e4.ui.tests.css.swt/src/org/eclipse/e4/ui/tests/css/swt/CTabFolderTest.java
CTabFolder folderToTest = createTestCTabFolder("CTabFolder { mruVisible: true}");
		assertEquals(true, folderToTest.getMRUVisible());
		assertEquals("true", engine.retrieveCSSProperty(folderToTest, "mruVisible", null));
		folderToTest.getShell().close();
		folderToTest = createTestCTabFolder("CTabFolder { mruVisible: false}");
		assertEquals("false", engine.retrieveCSSProperty(folderToTest, "mruVisible", null));
		assertEquals(false, folderToTest.getMRUVisible());
	}
	
	public void testMaximized() throws Exception {
		CTabFolder folderToTest = createTestCTabFolder("CTabFolder { maximized: true}");
		assertEquals(true, folderToTest.getMaximized());
		assertEquals("true", engine.retrieveCSSProperty(folderToTest, "maximized", null));
		folderToTest.getShell().close();
		folderToTest = createTestCTabFolder("CTabFolder { maximized: false}");
		assertEquals(false, folderToTest.getMaximized());
		assertEquals("false", engine.retrieveCSSProperty(folderToTest, "maximized", null));
	}
	
	public void testMinimized() throws Exception {
		CTabFolder folderToTest = createTestCTabFolder("CTabFolder { minimized: true}");
		assertEquals(true, folderToTest.getMinimized());
		assertEquals("true", engine.retrieveCSSProperty(folderToTest, "minimized", null));
		folderToTest.getShell().close();
		folderToTest = createTestCTabFolder("CTabFolder { minimized: false}");
		assertEquals(false, folderToTest.getMinimized());
		assertEquals("false", engine.retrieveCSSProperty(folderToTest, "minimized", null));
	}
	
	public void testSingle() throws Exception {