Add SetClient method implementation to InterfaceImpl.

mojo/public/cpp/bindings/lib/interface_impl_internal.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_IMPL_INTERNAL_H_
 #define MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_IMPL_INTERNAL_H_
 
 #include "mojo/public/cpp/bindings/error_handler.h"
 #include "mojo/public/cpp/bindings/interface_ptr.h"
 #include "mojo/public/cpp/system/macros.h"
 
 namespace mojo {
 namespace internal {
 
 template <typename Interface>
 class InterfaceImplState : public ErrorHandler {
  public:
+  typedef typename Interface::Client Client;
+
   explicit InterfaceImplState(WithErrorHandler<Interface>* instance)
       : router_(NULL),
+        client_(NULL),
         proxy_(NULL) {
     assert(instance);
     stub_.set_sink(instance);
   }
 
   virtual ~InterfaceImplState() {
     delete proxy_;
     if (router_) {
       router_->set_error_handler(NULL);
       delete router_;
     }
   }
 
   void BindProxy(
       InterfacePtr<Interface>* ptr,
       MojoAsyncWaiter* waiter = GetDefaultAsyncWaiter()) {
     MessagePipe pipe;
     ptr->Bind(pipe.handle0.Pass(), waiter);
     Bind(pipe.handle1.Pass(), waiter);
   }
 
   void Bind(ScopedMessagePipeHandle handle,
             MojoAsyncWaiter* waiter) {
     assert(!router_);
 
     router_ = new Router(handle.Pass(), waiter);
     router_->set_incoming_receiver(&stub_);
     router_->set_error_handler(this);
 
-    proxy_ = new typename Interface::Client_::Proxy_(router_);
+    proxy_ = new typename Client::Proxy_(router_);
 
     stub_.sink()->SetClient(proxy_);
   }
 
   Router* router() { return router_; }
 
+  void set_client(Client* client) { client_ = client; }
+  Client* client() { return client_; }
+
  private:
   virtual void OnConnectionError() MOJO_OVERRIDE {
     static_cast<WithErrorHandler<Interface>*>(stub_.sink())->
         OnConnectionError();
   }
 
   internal::Router* router_;
-  typename Interface::Client_::Proxy_* proxy_;
+  Client* client_;
+  typename Client::Proxy_* proxy_;
   typename Interface::Stub_ stub_;
 
   MOJO_DISALLOW_COPY_AND_ASSIGN(InterfaceImplState);
 };
 
 }  // namespace internal
 }  // namespace mojo
 
 #endif  // MOJO_PUBLIC_CPP_BINDINGS_LIB_INTERFACE_IMPL_INTERNAL_H_