ResizingHostObserver is created by the desktop environment together with other stubs.

remoting/host/desktop_session_proxy.cc

 // Copyright (c) 2012 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 "remoting/host/desktop_session_proxy.h"
 
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "base/platform_file.h"
 #include "base/process_util.h"
 #include "base/single_thread_task_runner.h"
 #include "ipc/ipc_channel_proxy.h"
 #include "ipc/ipc_message_macros.h"
 #include "media/video/capture/screen/screen_capture_data.h"
 #include "remoting/host/chromoting_messages.h"
 #include "remoting/host/client_session.h"
 #include "remoting/host/desktop_session_connector.h"
 #include "remoting/host/ipc_audio_capturer.h"
 #include "remoting/host/ipc_event_executor.h"
+#include "remoting/host/ipc_session_controller.h"
 #include "remoting/host/ipc_video_frame_capturer.h"
+#include "remoting/host/session_controller.h"
 #include "remoting/proto/audio.pb.h"
 #include "remoting/proto/control.pb.h"
 #include "remoting/proto/event.pb.h"
 
 #if defined(OS_WIN)
 #include "base/win/scoped_handle.h"
 #endif  // defined(OS_WIN)
 
 namespace remoting {
 
@@ skipping 23 matching lines @@
 }
 
 scoped_ptr<EventExecutor> DesktopSessionProxy::CreateEventExecutor(
     scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner) {
   DCHECK(caller_task_runner_->BelongsToCurrentThread());
 
   return scoped_ptr<EventExecutor>(new IpcEventExecutor(this));
 }
 
+scoped_ptr<SessionController> DesktopSessionProxy::CreateSessionController() {
+  return scoped_ptr<SessionController>(new IpcSessionController(this));
+}
+
 scoped_ptr<media::ScreenCapturer> DesktopSessionProxy::CreateVideoCapturer(
     scoped_refptr<base::SingleThreadTaskRunner> capture_task_runner,
     scoped_refptr<base::SingleThreadTaskRunner> encode_task_runner) {
   DCHECK(caller_task_runner_->BelongsToCurrentThread());
   DCHECK(!video_capture_task_runner_.get());
 
   video_capture_task_runner_ = capture_task_runner;
   return scoped_ptr<media::ScreenCapturer>(new IpcVideoFrameCapturer(this));
 }
 
@@ skipping 384 matching lines @@
 }
 
 // static
 void DesktopSessionProxyTraits::Destruct(
     const DesktopSessionProxy* desktop_session_proxy) {
   desktop_session_proxy->caller_task_runner_->DeleteSoon(FROM_HERE,
                                                          desktop_session_proxy);
 }
 
 }  // namespace remoting