Added a kEchoCancellation constraint to turn off the audio processing.

content/renderer/media/media_stream_audio_processor_options.cc

Index: content/renderer/media/media_stream_audio_processor_options.cc
diff --git a/content/renderer/media/media_stream_audio_processor_options.cc b/content/renderer/media/media_stream_audio_processor_options.cc
index e1474c029b37ddcf15c6b99892c8b9fa021dcbc9..eda4a390eb201dfe42e8819118b409c9cd51f0d0 100644
--- a/content/renderer/media/media_stream_audio_processor_options.cc
+++ b/content/renderer/media/media_stream_audio_processor_options.cc
@@ -8,57 +8,83 @@
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/path_service.h"
+#include "base/strings/string_number_conversions.h"
 #include "base/strings/utf_string_conversions.h"
 #include "content/common/media/media_stream_options.h"
+#include "content/renderer/media/media_stream_constraints_util.h"
+#include "content/renderer/media/media_stream_source.h"
 #include "content/renderer/media/rtc_media_constraints.h"
 #include "media/audio/audio_parameters.h"
-#include "third_party/WebKit/public/platform/WebMediaConstraints.h"
-#include "third_party/libjingle/source/talk/app/webrtc/mediaconstraintsinterface.h"
 #include "third_party/webrtc/modules/audio_processing/include/audio_processing.h"
 #include "third_party/webrtc/modules/audio_processing/typing_detection.h"
 
 namespace content {
 
+const char MediaAudioConstraints::kEchoCancellation[] = "echoCancellation";
+const char MediaAudioConstraints::kGoogEchoCancellation[] =
+    "googEchoCancellation";
+const char MediaAudioConstraints::kGoogExperimentalEchoCancellation[] =
+    "googEchoCancellation2";
+const char MediaAudioConstraints::kGoogAutoGainControl[] =
+    "googAutoGainControl";
+const char MediaAudioConstraints::kGoogExperimentalAutoGainControl[] =
+    "googAutoGainControl2";
+const char MediaAudioConstraints::kGoogNoiseSuppression[] =
+    "googNoiseSuppression";
+const char MediaAudioConstraints::kGoogExperimentalNoiseSuppression[] =
+    "googNoiseSuppression2";
+const char MediaAudioConstraints::kGoogHighpassFilter[] = "googHighpassFilter";
+const char MediaAudioConstraints::kGoogTypingNoiseDetection[] =
+    "googTypingNoiseDetection";
+const char MediaAudioConstraints::kGoogAudioMirroring[] = "googAudioMirroring";
+
 namespace {
 
 // Constant constraint keys which enables default audio constraints on
 // mediastreams with audio.
 struct {
   const char* key;
-  const char* value;
+  bool value;
 } const kDefaultAudioConstraints[] = {
-  { webrtc::MediaConstraintsInterface::kEchoCancellation,
-    webrtc::MediaConstraintsInterface::kValueTrue },
+  { MediaAudioConstraints::kEchoCancellation, true },
+  { MediaAudioConstraints::kGoogEchoCancellation, true },
 #if defined(OS_CHROMEOS) || defined(OS_MACOSX)
   // Enable the extended filter mode AEC on platforms with known echo issues.
-  { webrtc::MediaConstraintsInterface::kExperimentalEchoCancellation,
-    webrtc::MediaConstraintsInterface::kValueTrue },
+  { MediaAudioConstraints::kGoogExperimentalEchoCancellation, true },
+#else
+  { MediaAudioConstraints::kGoogExperimentalEchoCancellation, false },
 #endif
-  { webrtc::MediaConstraintsInterface::kAutoGainControl,
-    webrtc::MediaConstraintsInterface::kValueTrue },
-  { webrtc::MediaConstraintsInterface::kExperimentalAutoGainControl,
-    webrtc::MediaConstraintsInterface::kValueTrue },
-  { webrtc::MediaConstraintsInterface::kNoiseSuppression,
-    webrtc::MediaConstraintsInterface::kValueTrue },
-  { webrtc::MediaConstraintsInterface::kHighpassFilter,
-    webrtc::MediaConstraintsInterface::kValueTrue },
-  { webrtc::MediaConstraintsInterface::kTypingNoiseDetection,
-    webrtc::MediaConstraintsInterface::kValueTrue },
+  { MediaAudioConstraints::kGoogAutoGainControl, true },
+  { MediaAudioConstraints::kGoogExperimentalAutoGainControl, true },
+  { MediaAudioConstraints::kGoogNoiseSuppression, true },
+  { MediaAudioConstraints::kGoogHighpassFilter, true },
+  { MediaAudioConstraints::kGoogTypingNoiseDetection, true },
+  { MediaAudioConstraints::kGoogExperimentalNoiseSuppression, false },
 #if defined(OS_WIN)
-  { content::kMediaStreamAudioDucking,
-    webrtc::MediaConstraintsInterface::kValueTrue },
+  { kMediaStreamAudioDucking, true },
+#else
+  { kMediaStreamAudioDucking, false },
 #endif
 };
 
+bool IsAudioProcessingConstraint(const std::string& key) {
+  // |kMediaStreamAudioDucking| does not require audio processing.
+  return key != kMediaStreamAudioDucking;
+}
+
 } // namespace
 
-void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints) {
+// TODO(xians): Remove this method after the APM in WebRtc is deprecated.
+void MediaAudioConstraints::ApplyFixedAudioConstraints(
+    RTCMediaConstraints* constraints) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
     bool already_set_value;
     if (!webrtc::FindConstraint(constraints, kDefaultAudioConstraints[i].key,
                                 &already_set_value, NULL)) {
-      constraints->AddOptional(kDefaultAudioConstraints[i].key,
-          kDefaultAudioConstraints[i].value, false);
+      const std::string value = kDefaultAudioConstraints[i].value ?
+          webrtc::MediaConstraintsInterface::kValueTrue :
+          webrtc::MediaConstraintsInterface::kValueFalse;
+      constraints->AddOptional(kDefaultAudioConstraints[i].key, value, false);
     } else {
       DVLOG(1) << "Constraint " << kDefaultAudioConstraints[i].key
                << " already set to " << already_set_value;
@@ -66,21 +92,39 @@ void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints) {
   }
 }
 
-bool NeedsAudioProcessing(const blink::WebMediaConstraints& constraints,
-                          int effects) {
-  RTCMediaConstraints native_constraints(constraints);
-  ApplyFixedAudioConstraints(&native_constraints);
-  if (effects & media::AudioParameters::ECHO_CANCELLER) {
-    // If platform echo canceller is enabled, disable the software AEC.
-    native_constraints.AddOptional(
-        MediaConstraintsInterface::kEchoCancellation,
-        MediaConstraintsInterface::kValueFalse, true);
+MediaAudioConstraints::MediaAudioConstraints(
+    const blink::WebMediaConstraints& constraints, int effects)
+    : constraints_(constraints),
+      effects_(effects),
+      default_audio_processing_constraint_value_(true) {
+  // The default audio processing constraints are turned off when
+  // - gUM has a specific kMediaStreamSource, which is used by tab capture
+  //   and screen capture.
+  // - |kEchoCancellation| is explicitly set to false.
+  std::string value_str;
+  bool value_bool = false;
+  if ((GetConstraintValueAsString(constraints, kMediaStreamSource,
+                                  &value_str)) ||
+      (GetConstraintValueAsBoolean(constraints_, kEchoCancellation,
+                                   &value_bool) && !value_bool)) {
+    default_audio_processing_constraint_value_ = false;
   }
+}
+
+MediaAudioConstraints::~MediaAudioConstraints() {}
+
+// TODO(xians): Remove this method after the APM in WebRtc is deprecated.
+bool MediaAudioConstraints::NeedsAudioProcessing() {
+  if (GetEchoCancellationProperty())
+    return true;
+
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
-    bool value = false;
-    if (webrtc::FindConstraint(&native_constraints,
-                               kDefaultAudioConstraints[i].key, &value, NULL) &&
-        value) {
+    // |kEchoCancellation| and |kGoogEchoCancellation| have been convered by
+    // GetEchoCancellationProperty().
+    if (kDefaultAudioConstraints[i].key != kEchoCancellation &&
+        kDefaultAudioConstraints[i].key != kGoogEchoCancellation &&
+        IsAudioProcessingConstraint(kDefaultAudioConstraints[i].key) &&
+        GetProperty(kDefaultAudioConstraints[i].key)) {
       return true;
     }
   }
@@ -88,17 +132,81 @@ bool NeedsAudioProcessing(const blink::WebMediaConstraints& constraints,
   return false;
 }
 
-bool GetPropertyFromConstraints(const MediaConstraintsInterface* constraints,
-                                const std::string& key) {
+bool MediaAudioConstraints::GetProperty(const std::string& key) {
+  // Return the value if the constraint is specified in |constraints|,
+  // otherwise return the default value.
+  bool value = false;
+  if (!GetConstraintValueAsBoolean(constraints_, key, &value))
+    value = GetDefaultValueForConstraint(constraints_, key);
+
+  return value;
+}
+
+bool MediaAudioConstraints::GetEchoCancellationProperty() {
+  // If platform echo canceller is enabled, disable the software AEC.
+  if (effects_ & media::AudioParameters::ECHO_CANCELLER)
+    return false;
+
+  // If |kEchoCancellation| is specified in the constraints, it will
+  // override the value of |kGoogEchoCancellation|.
   bool value = false;
-  return webrtc::FindConstraint(constraints, key, &value, NULL) && value;
+  if (GetConstraintValueAsBoolean(constraints_, kEchoCancellation, &value))
+    return value;
+
+  return GetProperty(kGoogEchoCancellation);
+}
+
+bool MediaAudioConstraints::IsValid() {
+  blink::WebVector<blink::WebMediaConstraint> mandatory;
+  constraints_.getMandatoryConstraints(mandatory);
+  for (size_t i = 0; i < mandatory.size(); ++i) {
+    const std::string key = mandatory[i].m_name.utf8();
+    if (key == kMediaStreamSource || key == kMediaStreamSourceId ||
+        key == MediaStreamSource::kSourceId) {
+      // Ignore Chrome specific Tab capture and |kSourceId| constraints.
+      continue;
+    }
+
+    bool valid = false;
+    for (size_t j = 0; j < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++j) {
+      if (key == kDefaultAudioConstraints[j].key) {
+        bool value = false;
+        valid = GetMandatoryConstraintValueAsBoolean(constraints_, key, &value);
+        break;
+      }
+    }
+
+    if (!valid) {
+      DLOG(ERROR) << "Invalid MediaStream constraint. Name: " << key;
+      return false;
+    }
+  }
+
+  return true;
+}
+
+bool MediaAudioConstraints::GetDefaultValueForConstraint(
+    const blink::WebMediaConstraints& constraints, const std::string& key) {
+  // |kMediaStreamAudioDucking| is not restricted by
+  // |default_audio_processing_constraint_value_| since it does not require
+  // audio processing.
+  if (!default_audio_processing_constraint_value_ &&
+      IsAudioProcessingConstraint(key))
+    return false;
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
+    if (kDefaultAudioConstraints[i].key == key)
+      return kDefaultAudioConstraints[i].value;
+  }
+
+  return false;
 }
 
 void EnableEchoCancellation(AudioProcessing* audio_processing) {
 #if defined(OS_ANDROID) || defined(OS_IOS)
   const std::string group_name =
       base::FieldTrialList::FindFullName("ReplaceAECMWithAEC");
-  if (group_name.empty() || (group_name != "Enabled")) {
+  if (group_name.empty() || group_name != "Enabled") {
     // Mobile devices are using AECM.
     int err = audio_processing->echo_control_mobile()->set_routing_mode(
         webrtc::EchoControlMobile::kSpeakerphone);