Added an empty AudioTransportProxy to AudioState.

webrtc/audio/audio_state_unittest.cc

Index: webrtc/audio/audio_state_unittest.cc
diff --git a/webrtc/audio/audio_state_unittest.cc b/webrtc/audio/audio_state_unittest.cc
index 86a9176db39374f5f8038a338537faa615c5e083..39e29529825639904b95d2cd85b9f76891183043 100644
--- a/webrtc/audio/audio_state_unittest.cc
+++ b/webrtc/audio/audio_state_unittest.cc
@@ -11,6 +11,7 @@
 #include <memory>
 
 #include "webrtc/audio/audio_state.h"
+#include "webrtc/modules/audio_device/include/mock_audio_device.h"
 #include "webrtc/test/gtest.h"
 #include "webrtc/test/mock_voice_engine.h"
 
@@ -22,8 +23,13 @@ struct ConfigHelper {
   ConfigHelper() {
     EXPECT_CALL(voice_engine_,
         RegisterVoiceEngineObserver(testing::_)).WillOnce(testing::Return(0));
-    EXPECT_CALL(voice_engine_,
-        DeRegisterVoiceEngineObserver()).WillOnce(testing::Return(0));
+    EXPECT_CALL(voice_engine_, DeRegisterVoiceEngineObserver())
+        .WillOnce(testing::Return(0));
+    EXPECT_CALL(voice_engine_, audio_transport());
+    EXPECT_CALL(voice_engine_, audio_processing());
+    EXPECT_CALL(voice_engine_, audio_device_module());
+    ON_CALL(voice_engine_, audio_device_module())
+        .WillByDefault(Return(&mock_audio_device_));
     config_.voice_engine = &voice_engine_;
   }
   AudioState::Config& config() { return config_; }
@@ -31,6 +37,7 @@ struct ConfigHelper {
 
  private:
   testing::StrictMock<MockVoiceEngine> voice_engine_;
+  testing::NiceMock<webrtc::test::MockAudioDeviceModule> mock_audio_device_;
   AudioState::Config config_;
 };
 }  // namespace