Reduce chrome cras dbus call logs during device rebooting.

chrome/browser/extensions/api/audio/audio_service_chromeos.cc

 // Copyright (c) 2013 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 "chrome/browser/extensions/api/audio/audio_service.h"
 
 #include "base/callback.h"
 #include "base/memory/weak_ptr.h"
 #include "base/strings/string_number_conversions.h"
 #include "chromeos/audio/audio_device.h"
@@ skipping 39 matching lines @@
   virtual void OnActiveInputNodeChanged() OVERRIDE;
 
  private:
   void NotifyDeviceChanged();
 
   // Callback for CrasAudioClient::GetNodes().
   void OnGetNodes(const GetInfoCallback& callback,
                   const chromeos::AudioNodeList& audio_nodes,
                   bool success);
 
+  // ErrorCallback for CrasAudioClient::GetNodes().
+  void OnGetNodesError(const std::string& error_name,
+                       const std::string& error_msg);
+
   bool FindDevice(uint64 id, chromeos::AudioDevice* device);
   uint64 GetIdFromStr(const std::string& id_str);
 
   // List of observers.
   ObserverList<AudioService::Observer> observer_list_;
 
   chromeos::CrasAudioClient* cras_audio_client_;
   chromeos::CrasAudioHandler* cras_audio_handler_;
 
   // Note: This should remain the last member so it'll be destroyed and
@@ skipping 28 matching lines @@
   observer_list_.AddObserver(observer);
 }
 
 void AudioServiceImpl::RemoveObserver(AudioService::Observer* observer) {
   observer_list_.RemoveObserver(observer);
 }
 
 void AudioServiceImpl::StartGetInfo(const GetInfoCallback& callback) {
   DCHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));
   DCHECK(cras_audio_client_);
+  // TODO(jennyz,rkc): Replace cras_audio_client_ call with CrasAudioHandler
+  // Api call.
   if (cras_audio_client_)
     cras_audio_client_->GetNodes(base::Bind(&AudioServiceImpl::OnGetNodes,
                                             weak_ptr_factory_.GetWeakPtr(),
-                                            callback));
+                                            callback),
+                                 base::Bind(&AudioServiceImpl::OnGetNodesError,
+                                            weak_ptr_factory_.GetWeakPtr()));
 }
 
 void AudioServiceImpl::SetActiveDevices(const DeviceIdList& device_list) {
   DCHECK(cras_audio_handler_);
   if (!cras_audio_handler_)
     return;
 
   bool input_device_set = false;
   bool output_device_set = false;
 
@@ skipping 66 matching lines @@
         input_info.push_back(info);
       }
     }
   }
 
   DCHECK(!callback.is_null());
   if (!callback.is_null())
     callback.Run(output_info, input_info, success);
 }
 
+void AudioServiceImpl::OnGetNodesError(const std::string& error_name,
+                                       const std::string& error_msg) {
+}
+
 bool AudioServiceImpl::FindDevice(uint64 id, chromeos::AudioDevice* device) {
   chromeos::AudioDeviceList devices;
   cras_audio_handler_->GetAudioDevices(&devices);
 
   for (size_t i = 0; i < devices.size(); ++i) {
     if (devices[i].id == id) {
       *device = devices[i];
       return true;
     }
   }
@@ skipping 38 matching lines @@
 
 void AudioServiceImpl::NotifyDeviceChanged() {
   FOR_EACH_OBSERVER(AudioService::Observer, observer_list_, OnDeviceChanged());
 }
 
 AudioService* AudioService::CreateInstance() {
   return new AudioServiceImpl;
 }
 
 }  // namespace extensions