GYP->GN of audio_device_tests. Remove dead code. Fix new warnings.

webrtc/voice_engine/voe_base_impl.h

Index: webrtc/voice_engine/voe_base_impl.h
diff --git a/webrtc/voice_engine/voe_base_impl.h b/webrtc/voice_engine/voe_base_impl.h
index 192518a02532b01344d82690d83cdbbcd1a82832..93e1cf5e86cf8b219c6fac2e3278e5d06c130899 100644
--- a/webrtc/voice_engine/voe_base_impl.h
+++ b/webrtc/voice_engine/voe_base_impl.h
@@ -78,22 +78,6 @@ class VoEBaseImpl : public VoEBase,
                            size_t& nSamplesOut,
                            int64_t* elapsed_time_ms,
                            int64_t* ntp_time_ms) override;
-  int OnDataAvailable(const int voe_channels[],
-                      size_t number_of_voe_channels,
-                      const int16_t* audio_data,
-                      int sample_rate,
-                      size_t number_of_channels,
-                      size_t number_of_frames,
-                      int audio_delay_milliseconds,
-                      int current_volume,
-                      bool key_pressed,
-                      bool need_audio_processing) override;
-  void OnData(int voe_channel,
-              const void* audio_data,
-              int bits_per_sample,
-              int sample_rate,
-              size_t number_of_channels,
-              size_t number_of_frames) override;
   void PushCaptureData(int voe_channel,
                        const void* audio_data,
                        int bits_per_sample,