Create a RegisterViewAssociate method in ViewManager

services/ui/launcher/launch_instance.h

 // 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.
 
 #ifndef SERVICES_UI_LAUNCHER_LAUNCH_INSTANCE_H_
 #define SERVICES_UI_LAUNCHER_LAUNCH_INSTANCE_H_
 
 #include <memory>
 
 #include "base/callback.h"
 #include "mojo/public/cpp/application/application_delegate.h"
 #include "mojo/public/cpp/application/application_impl.h"
 #include "mojo/public/cpp/bindings/binding.h"
 #include "mojo/services/gfx/composition/interfaces/compositor.mojom.h"
 #include "mojo/services/native_viewport/interfaces/native_viewport.mojom.h"
 #include "mojo/services/native_viewport/interfaces/native_viewport_event_dispatcher.mojom.h"
 #include "mojo/services/ui/views/interfaces/view_manager.mojom.h"
 
 namespace launcher {
 
 class LauncherViewTree;
 
-class LaunchInstance : public mojo::NativeViewportEventDispatcher {
+class LaunchInstance : public mojo::NativeViewportEventDispatcher,
+                       public mojo::ui::ViewAssociateWatcher {
  public:
   LaunchInstance(mojo::ApplicationImpl* app_impl,
                  const std::string& app_url,
                  const base::Closure& shutdown_callback);
   ~LaunchInstance() override;
 
   void Launch();
 
+  // |ViewAssociateWatcher|
+  void OnViewAssociateConnectionError(
+      const mojo::String& label,
+      const OnViewAssociateConnectionErrorCallback& callback) override;
+
  private:
   // |NativeViewportEventDispatcher|:
   void OnEvent(mojo::EventPtr event,
                const mojo::Callback<void()>& callback) override;
 
   void OnCompositorConnectionError();
   void OnViewManagerConnectionError();
 
   void InitViewport();
   void OnViewportConnectionError();
@@ skipping 15 matching lines @@
   std::unique_ptr<LauncherViewTree> view_tree_;
 
   mojo::ui::ViewOwnerPtr client_view_owner_;
 
   DISALLOW_COPY_AND_ASSIGN(LaunchInstance);
 };
 
 }  // namespace launcher
 
 #endif  // SERVICES_UI_LAUNCHER_LAUNCH_INSTANCE_H_