Fix the volume controlling behaviors.

chrome/browser/chromeos/audio/audio_handler.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/chromeos/audio/audio_handler.h"
 
 #include <algorithm>
 #include <cmath>
 
 #include "base/logging.h"
@@ skipping 22 matching lines @@
 const int kPrefMuteOff = 0;
 const int kPrefMuteOn = 1;
 
 static AudioHandler* g_audio_handler = NULL;
 
 }  // namespace
 
 // static
 void AudioHandler::Initialize() {
   CHECK(!g_audio_handler);
-  g_audio_handler = new AudioHandler();
+#if defined(USE_CRAS)
+  g_audio_handler = new AudioHandler(new AudioMixerCras());
+#else
+  g_audio_handler = new AudioHandler(new AudioMixerAlsa());
+#endif
 }
 
 // static
 void AudioHandler::Shutdown() {
   // We may call Shutdown without calling Initialize, e.g. if we exit early.
   if (g_audio_handler) {
     delete g_audio_handler;
     g_audio_handler = NULL;
   }
 }
 
 // static
+void AudioHandler::InitializeForTesting(AudioMixer* mixer) {
+  CHECK(!g_audio_handler);
+  g_audio_handler = new AudioHandler(mixer);
+}
+
+// static
 AudioHandler* AudioHandler::GetInstance() {
   VLOG_IF(1, !g_audio_handler)
       << "AudioHandler::GetInstance() called with NULL global instance.";
   return g_audio_handler;
 }
 
 // static
 void AudioHandler::RegisterPrefs(PrefService* local_state) {
   if (!local_state->FindPreference(prefs::kAudioVolumePercent))
     local_state->RegisterDoublePref(prefs::kAudioVolumePercent,
                                     kDefaultVolumePercent,
                                     PrefService::UNSYNCABLE_PREF);
   if (!local_state->FindPreference(prefs::kAudioMute))
     local_state->RegisterIntegerPref(prefs::kAudioMute,
                                      kPrefMuteOff,
                                      PrefService::UNSYNCABLE_PREF);
 
   // Register the old decibel-based pref so we can clear it.
   // TODO(derat): Remove this after R20: http://crbug.com/112039
   if (!local_state->FindPreference(prefs::kAudioVolumeDb))
     local_state->RegisterDoublePref(prefs::kAudioVolumeDb,
                                     0,
                                     PrefService::UNSYNCABLE_PREF);
   local_state->ClearPref(prefs::kAudioVolumeDb);
   local_state->UnregisterPreference(prefs::kAudioVolumeDb);
 }
 
 double AudioHandler::GetVolumePercent() {
-  return mixer_->GetVolumePercent();
+  return (mixer_->IsMuted()) ? 0.0 : mixer_->GetVolumePercent();

[Daniel Erat, 2012/05/18 23:45:13]

I don't think that this UX decision should be reflected in AudioHandler.  Please
limit it to the UI code (i.e. just display 0 instead of the value from
GetVolumePercent() if IsMuted() is true).

[Jun Mukai, 2012/05/18 23:53:19]

Removed.  I will make the UI change in another CL.

 }
 
 void AudioHandler::SetVolumePercent(double volume_percent) {
   volume_percent = min(max(volume_percent, 0.0), 100.0);
   mixer_->SetVolumePercent(volume_percent);
   prefs_->SetDouble(prefs::kAudioVolumePercent, volume_percent);
   FOR_EACH_OBSERVER(VolumeObserver, volume_observers_, OnVolumeChanged());
 }
 
 void AudioHandler::AdjustVolumeByPercent(double adjust_by_percent) {
   SetVolumePercent(mixer_->GetVolumePercent() + adjust_by_percent);
 }
 
 bool AudioHandler::IsMuted() {
-  return mixer_->IsMuted();
+  return mixer_->GetVolumePercent() == 0 || mixer_->IsMuted();

[Daniel Erat, 2012/05/18 23:45:13]

ditto here

[Jun Mukai, 2012/05/18 23:53:19]

Removed too.

 }
 
 void AudioHandler::SetMuted(bool mute) {
   mixer_->SetMuted(mute);
   prefs_->SetInteger(prefs::kAudioMute, mute ? kPrefMuteOn : kPrefMuteOff);
   FOR_EACH_OBSERVER(VolumeObserver, volume_observers_, OnVolumeChanged());
 }
 
 void AudioHandler::AddVolumeObserver(VolumeObserver* observer) {
   volume_observers_.AddObserver(observer);
 }
 
 void AudioHandler::RemoveVolumeObserver(VolumeObserver* observer) {
   volume_observers_.RemoveObserver(observer);
 }
 
-AudioHandler::AudioHandler()
-#if defined(USE_CRAS)
-    : mixer_(new AudioMixerCras()),
-#else
-    : mixer_(new AudioMixerAlsa()),
-#endif
+AudioHandler::AudioHandler(AudioMixer* mixer)
+    : mixer_(mixer),
       prefs_(g_browser_process->local_state()) {
   mixer_->SetVolumePercent(prefs_->GetDouble(prefs::kAudioVolumePercent));
   mixer_->SetMuted(prefs_->GetInteger(prefs::kAudioMute) == kPrefMuteOn);
   mixer_->Init();
 }
 
 AudioHandler::~AudioHandler() {
   mixer_.reset();
 };
 
 }  // namespace chromeos