Bug 343003 Selection changes for shared parts may not be propagated if they were not originally rendered in the model
The search algorithm currently only iterates through containers for parts. This will not work for parts that are represented by placeholders.
tests/org.eclipse.e4.ui.tests/src/org/eclipse/e4/ui/tests/application/ESelectionServiceTest.java
private MPart part;
		private Object selection;
		public void reset() {
			part = null;
			selection = null;
		}
		public void selectionChanged(MPart part, Object selection) {
			this.part = part;
			this.selection = selection;
		}
		public MPart getPart() {
			return part;
		}
		public Object getSelection() {
			return selection;
		}
	}
}