Fix warnings, simplify ADM.

webrtc/modules/audio_device/audio_device_impl.h

Index: webrtc/modules/audio_device/audio_device_impl.h
diff --git a/webrtc/modules/audio_device/audio_device_impl.h b/webrtc/modules/audio_device/audio_device_impl.h
index 044ec4ed6b52cf8b086cb0b610a9f010b50fd2c1..034690f6b25b14c80ba8854b256de914efb8beb9 100644
--- a/webrtc/modules/audio_device/audio_device_impl.h
+++ b/webrtc/modules/audio_device/audio_device_impl.h
@@ -42,7 +42,7 @@ class AudioDeviceModuleImpl : public AudioDeviceModule {
   int32_t AttachAudioBuffer();
 
   AudioDeviceModuleImpl(const int32_t id, const AudioLayer audioLayer);
-  virtual ~AudioDeviceModuleImpl();
+  ~AudioDeviceModuleImpl() override;
 
   int64_t TimeUntilNextProcess() override;
   void Process() override;
@@ -178,7 +178,6 @@ class AudioDeviceModuleImpl : public AudioDeviceModule {
   int32_t SetLoudspeakerStatus(bool enable) override;
   int32_t GetLoudspeakerStatus(bool* enabled) const override;
 
-  bool BuiltInAECIsEnabled() const override;
   bool BuiltInAECIsAvailable() const override;
   int32_t EnableBuiltInAEC(bool enable) override;
   bool BuiltInAGCIsAvailable() const override;
@@ -186,8 +185,10 @@ class AudioDeviceModuleImpl : public AudioDeviceModule {
   bool BuiltInNSIsAvailable() const override;
   int32_t EnableBuiltInNS(bool enable) override;
 
+#if defined(WEBRTC_IOS)
   int GetPlayoutAudioParameters(AudioParameters* params) const override;
   int GetRecordAudioParameters(AudioParameters* params) const override;
+#endif  // WEBRTC_IOS
 
   int32_t Id() { return _id; }
 #if defined(WEBRTC_ANDROID)