Support custom message filtering on Mojo binding objects

mojo/public/cpp/bindings/associated_binding.h

Index: mojo/public/cpp/bindings/associated_binding.h
diff --git a/mojo/public/cpp/bindings/associated_binding.h b/mojo/public/cpp/bindings/associated_binding.h
index 1da50090cc1ac15221f33d04abc66608cbfd00fa..56f231a8bda86f23815140ee8890aa0d6956d6d1 100644
--- a/mojo/public/cpp/bindings/associated_binding.h
+++ b/mojo/public/cpp/bindings/associated_binding.h
@@ -23,6 +23,8 @@
 
 namespace mojo {
 
+class MessageReceiver;
+
 // Represents the implementation side of an associated interface. It is similar
 // to Binding, except that it doesn't own a message pipe handle.
 //
@@ -110,6 +112,11 @@ class AssociatedBinding {
         endpoint_client_->group_controller();
   }
 
+  void AddFilter(std::unique_ptr<MessageReceiver> filter) {
+    DCHECK(endpoint_client_);
+    endpoint_client_->AddFilter(std::move(filter));
+  }
+
   // Closes the associated interface. Puts this object into a state where it can
   // be rebound.
   void Close() {