Only log audio input silence state UMA stats for low latency mode and if not fake device.

media/audio/audio_input_controller.cc

Index: media/audio/audio_input_controller.cc
diff --git a/media/audio/audio_input_controller.cc b/media/audio/audio_input_controller.cc
index bcd9c7281e61d1ff3b3b66b73cf59f717c33296a..d662d6fb968b364e76af51d45d5da8a6dcf1e018 100644
--- a/media/audio/audio_input_controller.cc
+++ b/media/audio/audio_input_controller.cc
@@ -8,6 +8,7 @@
 #include "base/strings/stringprintf.h"
 #include "base/threading/thread_restrictions.h"
 #include "base/time/time.h"
+#include "media/audio/audio_parameters.h"
 #include "media/base/limits.h"
 #include "media/base/scoped_histogram_timer.h"
 #include "media/base/user_input_monitor.h"
@@ -85,6 +86,7 @@ AudioInputController::AudioInputController(EventHandler* handler,
       max_volume_(0.0),
       user_input_monitor_(user_input_monitor),
 #if defined(AUDIO_POWER_MONITORING)
+      log_silence_state_(false),
       silence_state_(SILENCE_STATE_NO_MEASUREMENT),
 #endif
       prev_key_down_count_(0) {
@@ -238,6 +240,21 @@ void AudioInputController::DoCreate(AudioManager* audio_manager,
   DoCreateForStream(audio_manager->MakeAudioInputStream(params, device_id));
 }
 
+void AudioInputController::DoCreateForLowLatency(AudioManager* audio_manager,
+                                                 const AudioParameters& params,
+                                                 const std::string& device_id) {
+  DCHECK(task_runner_->BelongsToCurrentThread());
+
+#if defined(AUDIO_POWER_MONITORING)
+  // We only log silence state UMA stats for low latency mode and if we use a
+  // real device.
+  if (params.format() != AudioParameters::AUDIO_FAKE)
+    log_silence_state_ = true;
+#endif
+
+  DoCreate(audio_manager, params, device_id);
+}
+
 void AudioInputController::DoCreateForStream(
     AudioInputStream* stream_to_control) {
   DCHECK(task_runner_->BelongsToCurrentThread());
@@ -329,10 +346,10 @@ void AudioInputController::DoClose() {
     user_input_monitor_->DisableKeyPressMonitoring();
 
 #if defined(AUDIO_POWER_MONITORING)
-  // Send UMA stats if we have enabled power monitoring.
-  if (audio_level_) {
+  // Send UMA stats if enabled.
+  if (log_silence_state_)
     LogSilenceState(silence_state_);
-  }
+  log_silence_state_ = false;
 #endif
 
   state_ = CLOSED;
@@ -503,26 +520,11 @@ void AudioInputController::DoLogAudioLevel(float level_dbfs) {
   std::string log_string = base::StringPrintf(
       "AIC::OnData: average audio level=%.2f dBFS", level_dbfs);
   static const float kSilenceThresholdDBFS = -72.24719896f;
-  if (level_dbfs < kSilenceThresholdDBFS) {
+  if (level_dbfs < kSilenceThresholdDBFS)
     log_string += " <=> no audio input!";
-    if (silence_state_ == SILENCE_STATE_NO_MEASUREMENT)
-      silence_state_ = SILENCE_STATE_ONLY_SILENCE;
-    else if (silence_state_ == SILENCE_STATE_ONLY_AUDIO)
-      silence_state_ = SILENCE_STATE_AUDIO_AND_SILENCE;
-    else
-      DCHECK(silence_state_ == SILENCE_STATE_ONLY_SILENCE ||
-             silence_state_ == SILENCE_STATE_AUDIO_AND_SILENCE);
-  } else {
-    if (silence_state_ == SILENCE_STATE_NO_MEASUREMENT)
-      silence_state_ = SILENCE_STATE_ONLY_AUDIO;
-    else if (silence_state_ == SILENCE_STATE_ONLY_SILENCE)
-      silence_state_ = SILENCE_STATE_AUDIO_AND_SILENCE;
-    else
-      DCHECK(silence_state_ == SILENCE_STATE_ONLY_AUDIO ||
-             silence_state_ == SILENCE_STATE_AUDIO_AND_SILENCE);
-  }
-
   handler_->OnLog(this, log_string);
+
+  UpdateSilenceState(level_dbfs < kSilenceThresholdDBFS);
 #endif
 }
 
@@ -555,6 +557,26 @@ bool AudioInputController::GetDataIsActive() {
 }
 
 #if defined(AUDIO_POWER_MONITORING)
+void AudioInputController::UpdateSilenceState(bool silence) {
+  if (silence) {
+    if (silence_state_ == SILENCE_STATE_NO_MEASUREMENT)
+      silence_state_ = SILENCE_STATE_ONLY_SILENCE;
+    else if (silence_state_ == SILENCE_STATE_ONLY_AUDIO)
+      silence_state_ = SILENCE_STATE_AUDIO_AND_SILENCE;
+    else
+      DCHECK(silence_state_ == SILENCE_STATE_ONLY_SILENCE ||
+             silence_state_ == SILENCE_STATE_AUDIO_AND_SILENCE);
+  } else {
+    if (silence_state_ == SILENCE_STATE_NO_MEASUREMENT)
+      silence_state_ = SILENCE_STATE_ONLY_AUDIO;
+    else if (silence_state_ == SILENCE_STATE_ONLY_SILENCE)
+      silence_state_ = SILENCE_STATE_AUDIO_AND_SILENCE;
+    else
+      DCHECK(silence_state_ == SILENCE_STATE_ONLY_AUDIO ||
+             silence_state_ == SILENCE_STATE_AUDIO_AND_SILENCE);
+  }
+}
+
 void AudioInputController::LogSilenceState(SilenceState value) {
   UMA_HISTOGRAM_ENUMERATION("Media.AudioInputControllerSessionSilenceReport",
                             value,