Make use of CreateInterfacePtrAndBind() where appropriate

mash/wm/window_manager_application.cc

 // Copyright 2015 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 "mash/wm/window_manager_application.h"
 
 #include <stdint.h>
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 66 matching lines @@
 void WindowManagerApplication::Initialize(mojo::ApplicationImpl* app) {
   app_ = app;
   tracing_.Initialize(app);
   window_manager_.reset(new WindowManagerImpl());
   // Don't bind to the WindowManager immediately. Wait for OnEmbed() first.
   mus::mojom::WindowManagerPtr window_manager;
   requests_.push_back(
       make_scoped_ptr(new mojo::InterfaceRequest<mus::mojom::WindowManager>(
           mojo::GetProxy(&window_manager))));
   user_window_controller_.reset(new UserWindowControllerImpl());
-  mus::mojom::WindowTreeHostClientPtr host_client;
-  host_client_binding_.Bind(GetProxy(&host_client));
-  mus::CreateSingleWindowTreeHost(app, std::move(host_client), this,
-                                  &window_tree_host_, std::move(window_manager),
-                                  window_manager_.get());
+  mus::CreateSingleWindowTreeHost(
+      app, host_client_binding_.CreateInterfacePtrAndBind(), this,
+      &window_tree_host_, std::move(window_manager), window_manager_.get());
 }
 
 bool WindowManagerApplication::ConfigureIncomingConnection(
     mojo::ApplicationConnection* connection) {
   connection->AddService<mash::wm::mojom::UserWindowController>(this);
   connection->AddService<mus::mojom::AcceleratorRegistrar>(this);
   connection->AddService<mus::mojom::WindowManager>(this);
   return true;
 }
 
@@ skipping 118 matching lines @@
     DCHECK_EQ(mus::LoWord(window->id()), container)
         << "Containers must be created before other windows!";
     window->SetBounds(root_->bounds());
     window->SetVisible(true);
     root_->AddChild(window);
   }
 }
 
 }  // namespace wm
 }  // namespace mash