Allow an external audio processing module to be used in WebRTC

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 b9f328259606f0a4afb0dac0cdf1f8bc62de4eca..6d7a086926e041d447f96e9cb804b95ca45964b3 100644
--- a/webrtc/voice_engine/voe_base_impl.h
+++ b/webrtc/voice_engine/voe_base_impl.h
@@ -28,12 +28,15 @@ class VoEBaseImpl : public VoEBase,
   int RegisterVoiceEngineObserver(VoiceEngineObserver& observer) override;
   int DeRegisterVoiceEngineObserver() override;
 
-  int Init(AudioDeviceModule* external_adm = nullptr,
-           AudioProcessing* audioproc = nullptr,
-           const rtc::scoped_refptr<AudioDecoderFactory>& decoder_factory =
-               nullptr) override;
+  int Init(
+      AudioDeviceModule* external_adm,
+      AudioProcessing* external_apm,
+      const rtc::scoped_refptr<AudioDecoderFactory>& decoder_factory) override;
   AudioProcessing* audio_processing() override {
-    return shared_->audio_processing();
+    // TODO(peah): Remove this when downstream dependencies have properly been
+    // resolved.
+    RTC_DCHECK(audio_processing_);
+    return audio_processing_.get();
   }
   AudioDeviceModule* audio_device_module() override {
     return shared_->audio_device();
@@ -121,6 +124,10 @@ class VoEBaseImpl : public VoEBase,
   rtc::CriticalSection callbackCritSect_;
   rtc::scoped_refptr<AudioDecoderFactory> decoder_factory_;
 
+  // TODO(peah): Remove this when upstream dependencies have properly been
+  // resolved.
+  rtc::scoped_refptr<AudioProcessing> audio_processing_;
+
   AudioFrame audioFrame_;
   voe::SharedData* shared_;
 };