Bug 321755 EPS adds a part without considering its placeholder if no target container or part stacks could be found
The summary probably makes no sense. Will deliver a fix with a test in a bit.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/EPartServiceTest.java
}
	public void testFindPart_PartInWindow() {
		MApplication application = createApplication("partId");
		MWindow window = application.getChildren().get(0);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		MPart part = partService.findPart("partId");
		assertNotNull(part);
		MPartStack partStack = (MPartStack) window.getChildren().get(0);
		assertEquals(partStack.getChildren().get(0), part);
		part = partService.findPart("invalidPartId");
		assertNull(part);
	}
	public void testFindPart_PartNotInWindow() {
		MApplication application = createApplication("partId");
		MWindow window = application.getChildren().get(0);
		getEngine().createGui(window);
		EPartService partService = (EPartService) window.getContext().get(
				EPartService.class.getName());
		MPart part = partService.findPart("invalidPartId");
		assertNull(part);
	}
	public void testFindPart_PartInAnotherWindow() {
		MApplication application = createApplication(
				new String[] { "partInWindow1" },
				new String[] { "partInWindow2" });
		MWindow window1 = application.getChildren().get(0);
		MWindow window2 = application.getChildren().get(1);
		getEngine().createGui(window1);