Use direct field access to trivial class properties

#KT-3845 Fixed

compiler/backend/src/org/jetbrains/jet/codegen/JvmCodegenUtil.java

@@ -273,7 +273,7 @@ public class JvmCodegenUtil {
         if (accessor == null) return true;
 
         // If the accessor is non-default (i.e. it has some code) we should call that accessor and not use direct access
-        if (!accessor.isDefault()) return false;
+        if (accessor.hasBody()) return false;
 
         // If the accessor is private or final, it can't be overridden in the subclass and thus we can use direct access
         return property.getVisibility() == Visibilities.PRIVATE || accessor.getModality() == FINAL;