Mojo C++ bindings: reduce references to AssociatedGroupController.

mojo/public/cpp/bindings/lib/interface_ptr_state.h

 // Copyright 2014 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.
 
 #ifndef MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_PTR_STATE_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_PTR_STATE_H_
 
 #include <stdint.h>
 
 #include <algorithm>  // For |std::swap()|.
@@ skipping 343 matching lines @@
     router_ = new MultiplexRouter(std::move(handle_), config, true, runner_);
     router_->SetMasterInterfaceName(Interface::Name_);
     endpoint_client_.reset(new InterfaceEndpointClient(
         router_->CreateLocalEndpointHandle(kMasterInterfaceId), nullptr,
         base::WrapUnique(new typename Interface::ResponseValidator_()), false,
         std::move(runner_),
         // The version is only queried from the client so the value passed here
         // will not be used.
         0u));
     proxy_.reset(new Proxy(endpoint_client_.get()));
-    proxy_->serialization_context()->group_controller =
-        endpoint_client_->group_controller();
+    if (Interface::PassesAssociatedKinds_) {
+      proxy_->serialization_context()->group_controller =
+          endpoint_client_->group_controller();
+    }
   }
 
   void OnQueryVersion(const base::Callback<void(uint32_t)>& callback,
                       uint32_t version) {
     version_ = version;
     callback.Run(version);
   }
 
   scoped_refptr<MultiplexRouter> router_;
 
   std::unique_ptr<InterfaceEndpointClient> endpoint_client_;
   std::unique_ptr<Proxy> proxy_;
 
   // |router_| (as well as other members above) is not initialized until
   // read/write with the message pipe handle is needed. |handle_| is valid
   // between the Bind() call and the initialization of |router_|.
   ScopedMessagePipeHandle handle_;
   scoped_refptr<base::SingleThreadTaskRunner> runner_;
 
   uint32_t version_;
 
   DISALLOW_COPY_AND_ASSIGN(InterfacePtrState);
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_PTR_STATE_H_