Bug 294493 XMI definition of part icon is ignored
The icon URI definition for parts seem to be ignored as the part tabs don't have any icons.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/UIStartupTest.java
protected Display display;
	@Override
	protected void setUp() throws Exception {
		display = Display.getDefault();
		super.setUp();
		while (display.readAndDispatch())
			;