Bug 334644 Cannot manually un/render a window that's directly under the application
Setting the 'toBeRendered' flag for a window that's a direct child of an application does nothing. The workaround is to manually de/construct it via the IPresentationEngine.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/workbench/PartRenderingEngineTests.java
IEclipseContext perspectiveContext2 = perspective2.getContext();
		assertEquals(partContext, perspectiveContext1.getActiveChild());
		assertEquals(perspectiveContext2, partContext.getParent());
		assertEquals(partContext, perspectiveContext2.getActiveChild());
		partService.hidePart(part);
		assertEquals(perspectiveContext1, partContext.getParent());
		assertEquals(partContext, perspectiveContext1.getActiveChild());
		assertNull(
				"perspective2 doesn't have any parts, it should not have an active child context",
				perspectiveContext2.getActiveChild());
	}
	private MWindow createWindowWithOneView(String partName) {
		final MWindow window = BasicFactoryImpl.eINSTANCE.createWindow();
		window.setHeight(300);
		window.setWidth(400);
		window.setLabel("MyWindow");
		MPartSashContainer sash = BasicFactoryImpl.eINSTANCE
				.createPartSashContainer();
		window.getChildren().add(sash);
		MPartStack stack = BasicFactoryImpl.eINSTANCE.createPartStack();
		sash.getChildren().add(stack);
		MPart contributedPart = BasicFactoryImpl.eINSTANCE.createPart();
		stack.getChildren().add(contributedPart);
		contributedPart.setLabel(partName);
		contributedPart
				.setContributionURI("platform:/plugin/org.eclipse.e4.ui.tests/org.eclipse.e4.ui.tests.workbench.SampleView");
		return window;
	}
}