Implement two new policies to control muting the audio I/O.

chrome/browser/chromeos/audio/audio_handler.cc

Index: chrome/browser/chromeos/audio/audio_handler.cc
diff --git a/chrome/browser/chromeos/audio/audio_handler.cc b/chrome/browser/chromeos/audio/audio_handler.cc
index 76eb60a9af31f2e8584ba5b8b559e42073439018..53457129c70943bd50eca58fc913b912d968976d 100644
--- a/chrome/browser/chromeos/audio/audio_handler.cc
+++ b/chrome/browser/chromeos/audio/audio_handler.cc
@@ -15,9 +15,13 @@
 #else
 #include "chrome/browser/chromeos/audio/audio_mixer_alsa.h"
 #endif
+#include "chrome/browser/chromeos/login/user_manager.h"
 #include "chrome/browser/prefs/pref_service.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/common/chrome_notification_types.h"
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
+#include "content/public/browser/notification_service.h"
 
 using std::max;
 using std::min;
@@ -90,6 +94,28 @@ void AudioHandler::RegisterPrefs(PrefService* local_state) {
   local_state->UnregisterPreference(prefs::kAudioVolumeDb);
 }
 
+// static
+void AudioHandler::RegisterUserPrefs(PrefService* user_prefs) {
+  user_prefs->RegisterBooleanPref(prefs::kAudioOutputDisabled,
+                                  false,
+                                  PrefService::UNSYNCABLE_PREF);
+  user_prefs->RegisterBooleanPref(prefs::kAudioCaptureDisabled,
+                                  false,
+                                  PrefService::UNSYNCABLE_PREF);
+}
+
+void AudioHandler::InitializePrefObservers(PrefService* user_prefs) {
+  // Don't do this for the login profile.
+  if (!chromeos::UserManager::Get()->IsUserLoggedIn())

[Mattias Nissler (ping if slow), 2012/08/28 12:24:24]

Isn't AudioHandler a singleton? Do you call InitializePrefObservers multiple
times on the same AudioHandler?

[pastarmovj, 2012/08/28 15:11:50]

Moved to local_state as suggested.

+    return;
+
+  user_prefs_ = user_prefs;
+  pref_change_registrar_.Init(user_prefs_);
+  pref_change_registrar_.Add(prefs::kAudioOutputDisabled, this);
+  pref_change_registrar_.Add(prefs::kAudioCaptureDisabled, this);
+  ApplyAudioPolicy();
+}
+
 double AudioHandler::GetVolumePercent() {
   return mixer_->GetVolumePercent();
 }
@@ -99,7 +125,7 @@ void AudioHandler::SetVolumePercent(double volume_percent) {
   if (IsMuted() && volume_percent > 0.0)
     SetMuted(false);
   mixer_->SetVolumePercent(volume_percent);
-  prefs_->SetDouble(prefs::kAudioVolumePercent, volume_percent);
+  local_state_->SetDouble(prefs::kAudioVolumePercent, volume_percent);
   FOR_EACH_OBSERVER(VolumeObserver, volume_observers_, OnVolumeChanged());
 }
 
@@ -112,11 +138,23 @@ bool AudioHandler::IsMuted() {
 }
 
 void AudioHandler::SetMuted(bool mute) {
-  mixer_->SetMuted(mute);
-  prefs_->SetInteger(prefs::kAudioMute, mute ? kPrefMuteOn : kPrefMuteOff);
+  if (!mixer_->IsMuteLocked()) {
+    mixer_->SetMuted(mute);
+    local_state_->SetInteger(prefs::kAudioMute,
+                             mute ? kPrefMuteOn : kPrefMuteOff);
+  }
   FOR_EACH_OBSERVER(VolumeObserver, volume_observers_, OnMuteToggled());
 }
 
+bool AudioHandler::IsMicMuted() {
+  return mixer_->IsCaptureMuted();
+}
+
+void AudioHandler::SetMicMuted(bool mute) {
+  if (!mixer_->IsCaptureMuteLocked())
+    mixer_->SetCaptureMuted(mute);
+}
+
 void AudioHandler::AddVolumeObserver(VolumeObserver* observer) {
   volume_observers_.AddObserver(observer);
 }
@@ -125,16 +163,59 @@ void AudioHandler::RemoveVolumeObserver(VolumeObserver* observer) {
   volume_observers_.RemoveObserver(observer);
 }
 
+void AudioHandler::Observe(int type,
+                           const content::NotificationSource& source,
+                           const content::NotificationDetails& details) {
+  if (type == chrome::NOTIFICATION_PROFILE_CREATED) {
+    Profile* profile = content::Source<Profile>(source).ptr();
+    if (!profile->IsOffTheRecord())
+      InitializePrefObservers(profile->GetPrefs());

[Mattias Nissler (ping if slow), 2012/08/28 12:24:24]

So when a second profile gets created, we override the existing settings? I
think a better way to do this would be to place these prefs in local_state after
all, which will see policy associated with the login user.

[pastarmovj, 2012/08/28 15:11:50]

Done.

+  }
+  if (type == chrome::NOTIFICATION_PREF_CHANGED) {

[Mattias Nissler (ping if slow), 2012/08/28 12:24:24]

else if

[pastarmovj, 2012/08/28 15:11:50]

Done.

+    std::string* pref_name = content::Details<std::string>(details).ptr();
+    if (*pref_name == prefs::kAudioOutputDisabled ||
+        *pref_name == prefs::kAudioCaptureDisabled) {
+      ApplyAudioPolicy();
+    }
+  }

[Mattias Nissler (ping if slow), 2012/08/28 12:24:24]

else {
  NOTREACHED() << type;
}

[pastarmovj, 2012/08/28 15:11:50]

Done.

+}
+
 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);
+      local_state_(g_browser_process->local_state()) {
+  mixer_->SetCaptureMuteLocked(false);
+  mixer_->SetCaptureMuted(false);
+  mixer_->SetMuteLocked(false);
+  mixer_->SetMuted(local_state_->GetInteger(prefs::kAudioMute) == kPrefMuteOn);
+  mixer_->SetVolumePercent(local_state_->GetDouble(prefs::kAudioVolumePercent));
   mixer_->Init();
+  registrar_.Add(this,
+                 chrome::NOTIFICATION_PROFILE_CREATED,
+                 content::NotificationService::AllSources());
 }
 
 AudioHandler::~AudioHandler() {
   mixer_.reset();
 };
 
+void AudioHandler::ApplyAudioPolicy() {
+  if (user_prefs_->GetBoolean(prefs::kAudioOutputDisabled)) {
+    mixer_->SetMuted(true);
+    mixer_->SetMuteLocked(true);
+  } else {
+    mixer_->SetMuteLocked(false);
+    mixer_->SetMuted(
+        local_state_->GetInteger(prefs::kAudioMute) == kPrefMuteOn);
+  }
+  FOR_EACH_OBSERVER(VolumeObserver, volume_observers_, OnMuteToggled());
+  if (user_prefs_->GetBoolean(prefs::kAudioCaptureDisabled)) {
+    mixer_->SetCaptureMuted(true);
+    mixer_->SetCaptureMuteLocked(true);
+  } else {
+    mixer_->SetCaptureMuteLocked(false);
+    mixer_->SetCaptureMuted(false);
+  }
+}
+
+
 }  // namespace chromeos