Added a kEchoCancellation constraint to turn off the audio processing.

content/renderer/media/webrtc/webrtc_local_audio_track_adapter_unittest.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "base/command_line.h"
 #include "content/public/common/content_switches.h"
+#include "content/renderer/media/mock_media_constraint_factory.h"
 #include "content/renderer/media/webrtc/webrtc_local_audio_track_adapter.h"
 #include "content/renderer/media/webrtc_local_audio_track.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "third_party/libjingle/source/talk/app/webrtc/mediastreaminterface.h"
 
 using ::testing::_;
 using ::testing::AnyNumber;
 
 namespace content {
@@ skipping 11 matching lines @@
                             int number_of_frames));
 };
 
 }  // namespace
 
 class WebRtcLocalAudioTrackAdapterTest : public ::testing::Test {
  public:
   WebRtcLocalAudioTrackAdapterTest()
       : params_(media::AudioParameters::AUDIO_PCM_LOW_LATENCY,
                 media::CHANNEL_LAYOUT_STEREO, 48000, 16, 480),
-        adapter_(WebRtcLocalAudioTrackAdapter::Create(std::string(), NULL)),
-        capturer_(WebRtcAudioCapturer::CreateCapturer(
-            -1, StreamDeviceInfo(MEDIA_DEVICE_AUDIO_CAPTURE, "", ""),
-            blink::WebMediaConstraints(), NULL, NULL)),
-        track_(new WebRtcLocalAudioTrack(adapter_, capturer_, NULL)) {}
+        adapter_(WebRtcLocalAudioTrackAdapter::Create(std::string(), NULL)) {
+    MockMediaConstraintFactory constraint_factory;
+    capturer_ = WebRtcAudioCapturer::CreateCapturer(
+        -1, StreamDeviceInfo(MEDIA_DEVICE_AUDIO_CAPTURE, "", ""),
+        constraint_factory.CreateWebMediaConstraints(), NULL, NULL);
+    track_.reset(new WebRtcLocalAudioTrack(adapter_, capturer_, NULL));
+  }
 
  protected:
   virtual void SetUp() OVERRIDE {
     track_->OnSetFormat(params_);
     EXPECT_TRUE(track_->GetAudioAdapter()->enabled());
   }
 
   media::AudioParameters params_;
   scoped_refptr<WebRtcLocalAudioTrackAdapter> adapter_;
   scoped_refptr<WebRtcAudioCapturer> capturer_;
@@ skipping 34 matching lines @@
   int signal_level = 0;
   EXPECT_FALSE(webrtc_track->GetSignalLevel(&signal_level));
 
   // Enable the audio processing in the audio track.
   CommandLine::ForCurrentProcess()->AppendSwitch(
       switches::kEnableAudioTrackProcessing);
   EXPECT_TRUE(webrtc_track->GetSignalLevel(&signal_level));
 }
 
 }  // namespace content