Move ADM Create() method to public interface.

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 a112e3e3bf68543fbfd3c38fae6faf9b25796ce2..044ec4ed6b52cf8b086cb0b610a9f010b50fd2c1 100644
--- a/webrtc/modules/audio_device/audio_device_impl.h
+++ b/webrtc/modules/audio_device/audio_device_impl.h
@@ -16,7 +16,6 @@
 #include <memory>
 
 #include "webrtc/base/checks.h"
-#include "webrtc/base/scoped_ref_ptr.h"
 #include "webrtc/modules/audio_device/audio_device_buffer.h"
 #include "webrtc/modules/audio_device/include/audio_device.h"
 
@@ -48,11 +47,6 @@ class AudioDeviceModuleImpl : public AudioDeviceModule {
   int64_t TimeUntilNextProcess() override;
   void Process() override;
 
-  // Factory methods (resource allocation/deallocation)
-  static rtc::scoped_refptr<AudioDeviceModule> Create(
-      const int32_t id,
-      const AudioLayer audioLayer = kPlatformDefaultAudio);
-
   // Retrieve the currently utilized audio layer
   int32_t ActiveAudioLayer(AudioLayer* audioLayer) const override;