Moved injection of AudioDecoderFactory into voe::Channel.

Channel's API remains unchanged, but the creation of a BuiltinAudioDecoderFactory is now in Channel. The next step would be to amend Channel's API (through CreateChannel, I believe) to allow an AudioDecoderFactory to be sent along.

BUG=webrtc:5805

Review-Url: https://codereview.webrtc.org/1992763002
Cr-Commit-Position: refs/heads/master@{#12893}
diff --git a/webrtc/modules/audio_coding/neteq/neteq.cc b/webrtc/modules/audio_coding/neteq/neteq.cc
index 2d1ce72..e3b9f8b 100644
--- a/webrtc/modules/audio_coding/neteq/neteq.cc
+++ b/webrtc/modules/audio_coding/neteq/neteq.cc
@@ -34,8 +34,11 @@
 
 // Creates all classes needed and inject them into a new NetEqImpl object.
 // Return the new object.
-NetEq* NetEq::Create(const NetEq::Config& config) {
-  return new NetEqImpl(config, NetEqImpl::Dependencies(config));
+NetEq* NetEq::Create(
+    const NetEq::Config& config,
+    const rtc::scoped_refptr<AudioDecoderFactory>& decoder_factory) {
+  return new NetEqImpl(config,
+                       NetEqImpl::Dependencies(config, decoder_factory));
 }
 
 }  // namespace webrtc