Fixed some NPEs for bug 452785: when EMF is unable to load referenced Ecore models, EClass.getEPackage() can return null

Signed-off-by: Miro Spönemann <miro.spoenemann@itemis.de>
[xtext][ui] Get rid of deprecation warnings

Change-Id: I65d683216478c18eb08b1f59295026f356506d34
Merge "Fixed some NPEs for bug 452785: when EMF is unable to load referenced Ecore models, EClass.getEPackage() can return null"
Merge "[xtext][ui] Get rid of deprecation warnings"