Remove AudioDeviceObserver and make ADM not inherit from the Module interface.

modules/audio_device/linux/audio_device_pulse_linux.cc

Index: modules/audio_device/linux/audio_device_pulse_linux.cc
diff --git a/modules/audio_device/linux/audio_device_pulse_linux.cc b/modules/audio_device/linux/audio_device_pulse_linux.cc
index ecbe63b97a8a591564a0df5e497bcd35331173da..9b16c696a7e98d4e380e76557d09a970052b8144 100644
--- a/modules/audio_device/linux/audio_device_pulse_linux.cc
+++ b/modules/audio_device/linux/audio_device_pulse_linux.cc
@@ -54,10 +54,6 @@ AudioDeviceLinuxPulse::AudioDeviceLinuxPulse()
       _sndCardPlayDelay(0),
       _sndCardRecDelay(0),
       _writeErrors(0),
-      _playWarning(0),
-      _playError(0),
-      _recWarning(0),
-      _recError(0),
       _deviceIndex(-1),
       _numPlayDevices(0),
       _numRecDevices(0),
@@ -160,11 +156,6 @@ AudioDeviceGeneric::InitStatus AudioDeviceLinuxPulse::Init() {
     return InitStatus::OTHER_ERROR;
   }
 
-  _playWarning = 0;
-  _playError = 0;
-  _recWarning = 0;
-  _recError = 0;
-
   // Get X display handle for typing detection
   _XDisplay = XOpenDisplay(NULL);
   if (!_XDisplay) {
@@ -1292,46 +1283,6 @@ bool AudioDeviceLinuxPulse::Playing() const {
   return (_playing);
 }
 
-bool AudioDeviceLinuxPulse::PlayoutWarning() const {
-  rtc::CritScope lock(&_critSect);
-  return (_playWarning > 0);
-}
-
-bool AudioDeviceLinuxPulse::PlayoutError() const {
-  rtc::CritScope lock(&_critSect);
-  return (_playError > 0);
-}
-
-bool AudioDeviceLinuxPulse::RecordingWarning() const {
-  rtc::CritScope lock(&_critSect);
-  return (_recWarning > 0);
-}
-
-bool AudioDeviceLinuxPulse::RecordingError() const {
-  rtc::CritScope lock(&_critSect);
-  return (_recError > 0);
-}
-
-void AudioDeviceLinuxPulse::ClearPlayoutWarning() {
-  rtc::CritScope lock(&_critSect);
-  _playWarning = 0;
-}
-
-void AudioDeviceLinuxPulse::ClearPlayoutError() {
-  rtc::CritScope lock(&_critSect);
-  _playError = 0;
-}
-
-void AudioDeviceLinuxPulse::ClearRecordingWarning() {
-  rtc::CritScope lock(&_critSect);
-  _recWarning = 0;
-}
-
-void AudioDeviceLinuxPulse::ClearRecordingError() {
-  rtc::CritScope lock(&_critSect);
-  _recError = 0;
-}
-
 // ============================================================================
 //                                 Private Methods
 // ============================================================================
@@ -2191,12 +2142,7 @@ bool AudioDeviceLinuxPulse::PlayThreadProcess() {
               NULL, (int64_t)0, PA_SEEK_RELATIVE) != PA_OK) {
         _writeErrors++;
         if (_writeErrors > 10) {
-          if (_playError == 1) {
-            LOG(LS_WARNING) << "pending playout error exists";
-          }
-          // Triggers callback from module process thread.
-          _playError = 1;
-          LOG(LS_ERROR) << "kPlayoutError message posted: _writeErrors="
+          LOG(LS_ERROR) << "Playout error: _writeErrors="
                         << _writeErrors
                         << ", error=" << LATE(pa_context_errno)(_paContext);
           _writeErrors = 0;
@@ -2240,12 +2186,7 @@ bool AudioDeviceLinuxPulse::PlayThreadProcess() {
                                 NULL, (int64_t)0, PA_SEEK_RELATIVE) != PA_OK) {
         _writeErrors++;
         if (_writeErrors > 10) {
-          if (_playError == 1) {
-            LOG(LS_WARNING) << "pending playout error exists";
-          }
-          // Triggers callback from module process thread.
-          _playError = 1;
-          LOG(LS_ERROR) << "kPlayoutError message posted: _writeErrors="
+          LOG(LS_ERROR) << "Playout error: _writeErrors="
                         << _writeErrors
                         << ", error=" << LATE(pa_context_errno)(_paContext);
           _writeErrors = 0;
@@ -2358,8 +2299,7 @@ bool AudioDeviceLinuxPulse::RecThreadProcess() {
       size_t sampleDataSize;
 
       if (LATE(pa_stream_peek)(_recStream, &sampleData, &sampleDataSize) != 0) {
-        _recError = 1;  // triggers callback from module process thread
-        LOG(LS_ERROR) << "RECORD_ERROR message posted, error = "
+        LOG(LS_ERROR) << "RECORD_ERROR, error = "
                       << LATE(pa_context_errno)(_paContext);
         break;
       }