[Mojo Video Capture] Stop service when last client disconnects.

services/video_capture/public/cpp/device_to_feedback_observer_adapter.cc

 // 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.
 
 #include "services/video_capture/public/cpp/device_to_feedback_observer_adapter.h"
 
 namespace video_capture {
 
 DeviceToFeedbackObserverAdapter::DeviceToFeedbackObserverAdapter(
-    mojom::DevicePtr device)
+    mojom::DevicePtr* device)
     : device_(std::move(device)) {}
 
 DeviceToFeedbackObserverAdapter::~DeviceToFeedbackObserverAdapter() = default;
 
 void DeviceToFeedbackObserverAdapter::OnUtilizationReport(int frame_feedback_id,
                                                           double utilization) {
-  device_->OnReceiverReportingUtilization(frame_feedback_id, utilization);
+  (*device_)->OnReceiverReportingUtilization(frame_feedback_id, utilization);
 }
 
 }  // namespace video_capture