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 320d1a6ba31d8296160a2a67b1c07523aa4d12ef..5065eea73aa7501948a8dfa17681d7e40c3f6365 100644
--- a/content/renderer/media/media_stream_audio_processor_options.cc
+++ b/content/renderer/media/media_stream_audio_processor_options.cc
@@ -7,57 +7,81 @@
 #include "base/files/file_path.h"
 #include "base/logging.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/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 kEchoCancellation[] = "echoCancellation";
+const char kGoogEchoCancellation[] = "googEchoCancellation";
+const char kGoogExperimentalEchoCancellation[] = "googEchoCancellation2";
+const char kGoogAutoGainControl[] = "googAutoGainControl";
+const char kGoogExperimentalAutoGainControl[] = "googAutoGainControl2";
+const char kGoogNoiseSuppression[] = "googNoiseSuppression";
+const char kGoogExperimentalNoiseSuppression[] = "googNoiseSuppression2";
+const char kGoogHighpassFilter[] = "googHighpassFilter";
+const char kGoogTypingNoiseDetection[] = "googTypingNoiseDetection";
+const char 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 },
+  { kEchoCancellation, true },
+  { 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 },
+  { kGoogExperimentalEchoCancellation, true },
+#else
+  { 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 },
+  { kGoogAutoGainControl, true },
+  { kGoogExperimentalAutoGainControl, true },
+  { kGoogNoiseSuppression, true },
+  { kGoogHighpassFilter, true },
+  { kGoogTypingNoiseDetection, true },
 #if defined(OS_WIN)
-  { content::kMediaStreamAudioDucking,
-    webrtc::MediaConstraintsInterface::kValueTrue },
+  { content::kMediaStreamAudioDucking, true },

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

remove content:: prefix here and in the line below.

[no longer working on chromium, 2014/04/11 08:56:30]

Done.

+#else
+  { content::kMediaStreamAudioDucking, false },

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

why adding this?

[no longer working on chromium, 2014/04/11 08:56:30]

I think it is good to explicitly define the default values to all constraints in
one place, and we know exactly what will be set to true or false.

If you disagree, I can fall back to the previous code, which implicitly sets to
false if the key could not be found in kDefaultAudioConstraints.

 #endif
 };
 
+bool GetDefaultValueForConstraint(const std::string& key,
+                                  MediaStreamType type) {

[perkj_chrome, 2014/04/08 10:28:12]

You can read the type from the original constrains instead. Not sure if that is
better or not... 

[no longer working on chromium, 2014/04/11 08:56:30]

Done. 

+  // Audio processing is false for gUM of non-MEDIA_DEVICE_AUDIO_CAPTURE.
+  if (type != MEDIA_DEVICE_AUDIO_CAPTURE)

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

the name of the function is GetDefaultValueForConstraint so this check seems a
bit strange.  Is it needed and is the MediaStreamType parameter really needed
since we're in the audio processor source file?

[no longer working on chromium, 2014/04/11 08:56:30]

Per pointed out that we should be able to get the type from the constraints, so
I remove the type.

But we still need to check if that is from default source or not, since for gUM
of tab source or system source, the default value will be false.

+    return false;
+
+  for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
+    if (kDefaultAudioConstraints[i].key == key)
+      return kDefaultAudioConstraints[i].value;
+  }
+
+  return false;

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

I'm a bit wary of this sort of implementation.  I'd rather that the function
accepts a default in the case where the constraint is not found and then return
the default here.

[no longer working on chromium, 2014/04/11 08:56:30]

Done.

+}
+
 } // namespace
 
+// TODO(xians): Remove this method after the APM in WebRtc is deprecated.
 void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints) {

[no longer working on chromium, 2014/04/08 10:02:53]

These two methods are still used in WebRtcAudioCapturer and
MediaStreamDependencyFactory for the old path, we can't remove them until the
old path goes away.

   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);
+          base::IntToString(kDefaultAudioConstraints[i].value), false);

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

ugh, isn't this is a big change in functionality?  We can't start mixing
integers and strings and then feed either user provided values or generated
values through the same parse routines.

[no longer working on chromium, 2014/04/11 08:56:30]

Right, we have to keep using the webrtc::MediaConstraintsInterface::kValueXXX

[tommi (sloooow) - chröme, 2014/04/11 12:51:16]

I don't think you understand my comments.  You're changing "True" to "1" here. 
They are not the same.
If the constraint exists and is set to "True" or "False" you cannot convert that
to an integer in the same way you'd convert "1" and "0".

     } else {
       DVLOG(1) << "Constraint " << kDefaultAudioConstraints[i].key
                << " already set to " << already_set_value;
@@ -65,21 +89,13 @@ void ApplyFixedAudioConstraints(RTCMediaConstraints* constraints) {
   }
 }
 
+// TODO(xians): Remove this method after the APM in WebRtc is deprecated.
 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);
-  }
+                          int effects, MediaStreamType type) {
   for (size_t i = 0; i < ARRAYSIZE_UNSAFE(kDefaultAudioConstraints); ++i) {
-    bool value = false;
-    if (webrtc::FindConstraint(&native_constraints,
-                               kDefaultAudioConstraints[i].key, &value, NULL) &&
-        value) {
+    if (GetPropertyFromConstraints(constraints,
+                                   kDefaultAudioConstraints[i].key,
+                                   effects, type)) {
       return true;
     }
   }
@@ -87,10 +103,21 @@ bool NeedsAudioProcessing(const blink::WebMediaConstraints& constraints,
   return false;
 }
 
-bool GetPropertyFromConstraints(const MediaConstraintsInterface* constraints,
-                                const std::string& key) {
-  bool value = false;
-  return webrtc::FindConstraint(constraints, key, &value, NULL) && value;
+bool GetPropertyFromConstraints(const blink::WebMediaConstraints& constraints,
+                                const std::string& key,
+                                int effects,
+                                MediaStreamType type) {
+  if (effects & media::AudioParameters::ECHO_CANCELLER &&

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

Please get Andrew to review this.

The name of this method is GetPropertyFromConstraints and that does not reflect
this sort of special casing.  At the very least this check is in the wrong place
and I think that there was previously a better way to do what you want.

[no longer working on chromium, 2014/04/11 08:56:30]

Will do.
I agree. Previously we mapped the blink constraints to a writable
RTCMediaConstraints, and modified the AEC constraint if effect was on, but we
can't do it any more with the new code since we need to deal with the
non-writable blink constraint directly.
I will check with Andrew to see if we can have another better alternative here.

+      key == kGoogEchoCancellation) {
+    // If platform echo canceller is enabled, disable the software AEC.
+    return false;

[perkj_chrome, 2014/04/08 10:28:12]

What does this mean? Can echo cancellation on/off not be controlled from js? 

[no longer working on chromium, 2014/04/11 08:56:30]

Yes, when the effect is on, we need to disable the software AEC.

+  }
+
+  // Return the value if the constraint is specified in |constraints|,
+  // otherwise return the default value.
+  bool value = GetDefaultValueForConstraint(key, type);

[tommi (sloooow) - chröme, 2014/04/08 10:49:30]

better to do:

if (!GetConstraintValue(constraints, key, &value))
  value = GetDefaultValueForConstraint(key, type);

[no longer working on chromium, 2014/04/11 08:56:30]

Done.

+  GetConstraintValue(constraints, key, &value);
+  return value;
 }
 
 void EnableEchoCancellation(AudioProcessing* audio_processing) {