Delete method DecoderDatabase::RegisterPayload(...NetEqDecoder...)

Bug: webrtc:10185
Change-Id: I69ce40b1c7267b039cd1d2237c5d5bbae3a81875
Reviewed-on: https://webrtc-review.googlesource.com/c/116683
Commit-Queue: Niels Moller <nisse@webrtc.org>
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Ivo Creusen <ivoc@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26208}

modules/audio_coding/neteq/tools/neteq_test.h

@@ -67,7 +67,7 @@ class NetEqSimulationEndedCallback {
 // directed to an AudioSink object.
 class NetEqTest : public NetEqSimulator {
  public:
-  using DecoderMap = std::map<int, std::pair<NetEqDecoder, std::string> >;
+  using DecoderMap = std::map<int, SdpAudioFormat>;
 
   struct Callbacks {
     NetEqTestErrorCallback* error_callback = nullptr;