Added volume adjust sound behind the flag.

chrome/browser/ui/ash/volume_controller_chromeos.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 "chrome/browser/ui/ash/volume_controller_chromeos.h"
 
 #include "ash/ash_switches.h"
+#include "base/command_line.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/extensions/api/system_private/system_private_api.h"
+#include "chromeos/audio/chromeos_sounds.h"
+#include "chromeos/chromeos_switches.h"
 #include "content/public/browser/user_metrics.h"
+#include "grit/browser_resources.h"
+#include "media/audio/sounds/sounds_manager.h"
+#include "ui/base/resource/resource_bundle.h"
 
 using chromeos::CrasAudioHandler;
 
 namespace {
 
 // Percent by which the volume should be changed when a volume key is pressed.
 const double kStepPercentage = 4.0;
 
+void PlayVolumeAdjustSound() {
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          chromeos::switches::kEnableVolumeAdjustSound)) {
+    media::SoundsManager::Get()->Play(chromeos::SOUND_VOLUME_ADJUST);
+  }
+}
+
 }  // namespace
 
 VolumeController::VolumeController() {
   CrasAudioHandler::Get()->AddAudioObserver(this);
+  ui::ResourceBundle& bundle = ui::ResourceBundle::GetSharedInstance();
+  media::SoundsManager::Get()->Initialize(
+      chromeos::SOUND_VOLUME_ADJUST,
+      bundle.GetRawDataResource(IDR_SOUND_VOLUME_ADJUST_WAV));
 }
 
 VolumeController::~VolumeController() {
   if (CrasAudioHandler::IsInitialized())
     CrasAudioHandler::Get()->RemoveAudioObserver(this);
 }
 
 bool VolumeController::HandleVolumeMute(const ui::Accelerator& accelerator) {
   if (accelerator.key_code() == ui::VKEY_VOLUME_MUTE)
     content::RecordAction(content::UserMetricsAction("Accel_VolumeMute_F8"));
 
   CrasAudioHandler::Get()->SetOutputMute(true);
   return true;
 }
 
 bool VolumeController::HandleVolumeDown(const ui::Accelerator& accelerator) {
   if (accelerator.key_code() == ui::VKEY_VOLUME_DOWN)
     content::RecordAction(content::UserMetricsAction("Accel_VolumeDown_F9"));
 
   CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
   if (audio_handler->IsOutputMuted()) {
     audio_handler->SetOutputVolumePercent(0);
   } else {
     audio_handler->AdjustOutputVolumeByPercent(-kStepPercentage);
     if (audio_handler->IsOutputVolumeBelowDefaultMuteLvel())
       audio_handler->SetOutputMute(true);
   }
+
+  PlayVolumeAdjustSound();

[DaleCurtis, 2014/01/02 20:11:17]

Generally these stop playing when volume reaches the minimum level, no?

[ygorshenin1, 2014/01/09 19:26:57]

Done.

   return true;
 }
 
 bool VolumeController::HandleVolumeUp(const ui::Accelerator& accelerator) {
   if (accelerator.key_code() == ui::VKEY_VOLUME_UP)
     content::RecordAction(content::UserMetricsAction("Accel_VolumeUp_F10"));
 
   CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
   if (audio_handler->IsOutputMuted()) {
       audio_handler->SetOutputMute(false);
       audio_handler->AdjustOutputVolumeToAudibleLevel();
   } else {
     audio_handler->AdjustOutputVolumeByPercent(kStepPercentage);
   }
 
+  PlayVolumeAdjustSound();

[DaleCurtis, 2014/01/02 20:11:17]

Ditto, stop at 100% ?

[ygorshenin1, 2014/01/09 19:26:57]

Done.

   return true;
 }
 
 void VolumeController::OnOutputVolumeChanged() {
   CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
   extensions::DispatchVolumeChangedEvent(
       audio_handler->GetOutputVolumePercent(),
       audio_handler->IsOutputMuted());
 }
 
 void VolumeController::OnOutputMuteChanged() {
   CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
   extensions::DispatchVolumeChangedEvent(
       audio_handler->GetOutputVolumePercent(),
       audio_handler->IsOutputMuted());
 }