Allow hooking the queueable collection logic

This allows the use of parent/child Models in the same collection, to be properly serialized using the parent model (given a proper trait that facilitates the new function).
Parent/child models as implemented in for example (https://github.com/calebporzio/parental) currently cause serialization errors when attempting to queue or otherwise serialize a collection containing them. 

This hook would allow us to alleviate the issue.

Author: Smoggert

src/Illuminate/Database/Eloquent/Collection.php

@@ -665,17 +665,33 @@ public function getQueueableClass()
             return;
         }
 
-        $class = get_class($this->first());
+        $class = $this->getModelClass($this->first());
 
         $this->each(function ($model) use ($class) {
-            if (get_class($model) !== $class) {
+            if ($this->getModelClass($model) !== $class) {
                 throw new LogicException('Queueing collections with multiple model types is not supported.');
             }
         });
 
         return $class;
     }
 
+    /**
+     * Get the identifiers for all of the entities.
+     *
+     * @return array<int, mixed>
+     */
+    protected function getModelClass($model)
+    {
+        if(method_exists($model,'getClassNameForSerialization')) {
+                return $model->getClassNameForSerialization();
+        }
+        
+        return get_class($model);
+    }
+    
+    
+
     /**
      * Get the identifiers for all of the entities.
      *