fix entity server crash

Author: HifiExperiments

libraries/entities/src/EntityItem.h.in

@@ -452,7 +452,9 @@ public:
         _updateScriptUserDataOperator = updateScriptUserDataOperator;
     }
     static void updateScriptUserData(const EntityItemID& entityID, const QString& scriptURL, const QString& userData) {
-        _updateScriptUserDataOperator(entityID, scriptURL, userData);
+        if (_updateScriptUserDataOperator) {
+            _updateScriptUserDataOperator(entityID, scriptURL, userData);
+        }
     }
 
 signals:

libraries/entities/src/ScriptEntityItem.cpp.in

@@ -197,6 +197,18 @@ bool ScriptEntityItem::getEnabled() const {
 }
 
 void ScriptEntityItem::updateScript() {
+    const auto tree = getTree();
+    if (!tree) {
+        _updateNeeded = true;
+        return;
+    }
+
+    // We only support client-side Script entities for now
+    if (!tree->getIsClient()) {
+        _updateNeeded = false;
+        return;
+    }
+
     QUuid parentID = getParentID();
     QUuid runningParentID;
     QString runningScriptURL;