Eliminate deferred destruction of AssociatedGroupController

mojo/public/cpp/bindings/lib/associated_group_controller.cc

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "mojo/public/cpp/bindings/associated_group_controller.h"
 
 #include "mojo/public/cpp/bindings/associated_group.h"
 
 namespace mojo {
 
-AssociatedGroupController::AssociatedGroupController(
-    scoped_refptr<base::SingleThreadTaskRunner> task_runner)
-    : base::RefCountedDeleteOnMessageLoop<AssociatedGroupController>(
-          task_runner) {}
-
 AssociatedGroupController::~AssociatedGroupController() {}
 
 std::unique_ptr<AssociatedGroup>
 AssociatedGroupController::CreateAssociatedGroup() {
   std::unique_ptr<AssociatedGroup> group(new AssociatedGroup);
   group->controller_ = this;
   return group;
 }
 
 ScopedInterfaceEndpointHandle
 AssociatedGroupController::CreateScopedInterfaceEndpointHandle(
     InterfaceId id,
     bool is_local) {
   return ScopedInterfaceEndpointHandle(id, is_local, this);
 }
 
 }  // namespace mojo