[101] Fix refresh issue in Model Explorer

Bug: #101
Signed-off-by: Pierre-Charles David <pierre-charles.david@obeo.fr>

plugins/org.eclipse.sirius.ui/src/org/eclipse/sirius/ui/tools/internal/views/common/navigator/SiriusCommonContentProvider.java

@@ -1066,11 +1066,7 @@ public boolean apply(Notification notification) {
         }
 
         private boolean isSemanticChange(Resource resource) {
-            boolean result = false;
-            if (resource != null) {
-                allSemanticResources.contains(resource);
-            }
-            return result;
+            return resource != null && allSemanticResources.contains(resource);
         }
 
     }