Add the allow_add_remove parameter to the get_serializer method

docs/api-guide/generic-views.md

@@ -187,7 +187,7 @@ Remember that the `pre_save()` method is not called by `GenericAPIView` itself,
 You won't typically need to override the following methods, although you might need to call into them if you're writing custom views using `GenericAPIView`.
 
 * `get_serializer_context(self)` - Returns a dictionary containing any extra context that should be supplied to the serializer.  Defaults to including `'request'`, `'view'` and `'format'` keys.
-* `get_serializer(self, instance=None, data=None, files=None, many=False, partial=False)` - Returns a serializer instance.
+* `get_serializer(self, instance=None, data=None, files=None, many=False, partial=False, allow_add_remove=False)` - Returns a serializer instance.
 * `get_pagination_serializer(self, page)` - Returns a serializer instance to use with paginated data.
 * `paginate_queryset(self, queryset)` - Paginate a queryset if required, either returning a page object, or `None` if pagination is not configured for this view.
 * `filter_queryset(self, queryset)` - Given a queryset, filter it with whichever filter backends are in use, returning a new queryset.

rest_framework/generics.py

@@ -90,8 +90,8 @@ class GenericAPIView(views.APIView):
             'view': self
         }
 
-    def get_serializer(self, instance=None, data=None,
-                       files=None, many=False, partial=False):
+    def get_serializer(self, instance=None, data=None, files=None, many=False,
+                       partial=False, allow_add_remove=False):
         """
         Return the serializer instance that should be used for validating and
         deserializing input, and for serializing output.
@@ -99,7 +99,9 @@ class GenericAPIView(views.APIView):
         serializer_class = self.get_serializer_class()
         context = self.get_serializer_context()
         return serializer_class(instance, data=data, files=files,
-                                many=many, partial=partial, context=context)
+                                many=many, partial=partial,
+                                allow_add_remove=allow_add_remove,
+                                context=context)
 
     def get_pagination_serializer(self, page):
         """