Changed DatasetFieldType.isControlledVocabulary() to return allowCont…

…rolledVocabulary instead of looking up complete list of terms to see if it is empty

src/main/java/edu/harvard/iq/dataverse/DatasetFieldType.java

@@ -284,7 +284,7 @@ public void setDisplayOnCreate(boolean displayOnCreate) {
     }
 
     public boolean isControlledVocabulary() {
-        return controlledVocabularyValues != null && !controlledVocabularyValues.isEmpty();
+        return allowControlledVocabulary;
     }
 
     /**