Resubmit 'Refactor the TrayAudio code so that it can be used by other platforms.'

ash/system/chromeos/audio/tray_audio_delegate_chromeos.cc

+// Copyright 2014 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 "ash/system/chromeos/audio/tray_audio_delegate_chromeos.h"
+
+#include "chromeos/audio/cras_audio_handler.h"
+#include "grit/ash_resources.h"
+#include "grit/ash_strings.h"
+
+using chromeos::CrasAudioHandler;
+
+namespace ash  {
+namespace system {
+
+void TrayAudioDelegateChromeOs::AdjustOutputVolumeToAudibleLevel() {
+  CrasAudioHandler::Get()->AdjustOutputVolumeToAudibleLevel();
+}
+
+int TrayAudioDelegateChromeOs::GetOutputDefaultVolumeMuteLevel() {
+  return CrasAudioHandler::Get()->GetOutputDefaultVolumeMuteThreshold();
+}
+
+int TrayAudioDelegateChromeOs::GetOutputVolumeLevel() {
+  return CrasAudioHandler::Get()->GetOutputVolumePercent();
+}
+
+int TrayAudioDelegateChromeOs::GetActiveOutputDeviceIconId() {
+  chromeos::AudioDevice device;
+  if (!CrasAudioHandler::Get()->GetActiveOutputDevice(&device))
+    return kNoAudioDeviceIcon;
+
+  if (device.type == chromeos::AUDIO_TYPE_HEADPHONE)
+    return IDR_AURA_UBER_TRAY_AUDIO_HEADPHONE;
+  else if (device.type == chromeos::AUDIO_TYPE_USB)
+    return IDR_AURA_UBER_TRAY_AUDIO_USB;
+  else if (device.type == chromeos::AUDIO_TYPE_BLUETOOTH)
+    return IDR_AURA_UBER_TRAY_AUDIO_BLUETOOTH;
+  else if (device.type == chromeos::AUDIO_TYPE_HDMI)
+    return IDR_AURA_UBER_TRAY_AUDIO_HDMI;
+  else
+    return kNoAudioDeviceIcon;
+}
+
+
+bool TrayAudioDelegateChromeOs::HasAlternativeSources() {
+  CrasAudioHandler* audio_handler = CrasAudioHandler::Get();
+  return (audio_handler->has_alternative_output() ||
+          audio_handler->has_alternative_input());
+}
+
+bool TrayAudioDelegateChromeOs::IsOutputAudioMuted() {
+  return CrasAudioHandler::Get()->IsOutputMuted();
+}
+
+void TrayAudioDelegateChromeOs::SetOutputAudioIsMuted(bool is_muted) {
+  CrasAudioHandler::Get()->SetOutputMute(is_muted);
+}
+
+void TrayAudioDelegateChromeOs::SetOutputVolumeLevel(int level) {
+  CrasAudioHandler::Get()->SetOutputVolumePercent(level);
+}
+
+}  // namespace system
+}  // namespace ash