Delete video_coding_robustness_unittest.cc

BUG=none

Review-Url: https://codereview.webrtc.org/2755803004
Cr-Commit-Position: refs/heads/master@{#17312}
diff --git a/webrtc/modules/video_coding/video_coding_impl.h b/webrtc/modules/video_coding/video_coding_impl.h
index f1dbd13..5e547df 100644
--- a/webrtc/modules/video_coding/video_coding_impl.h
+++ b/webrtc/modules/video_coding/video_coding_impl.h
@@ -144,8 +144,6 @@
 
 class VideoReceiver : public Module {
  public:
-  typedef VideoCodingModule::ReceiverRobustness ReceiverRobustness;
-
   VideoReceiver(Clock* clock,
                 EventFactory* event_factory,
                 EncodedImageCallback* pre_decode_image_callback,
@@ -180,8 +178,11 @@
   int32_t SetRenderDelay(uint32_t timeMS);
   int32_t Delay() const;
 
-  int SetReceiverRobustnessMode(ReceiverRobustness robustnessMode,
-                                VCMDecodeErrorMode errorMode);
+  // DEPRECATED.
+  int SetReceiverRobustnessMode(
+      VideoCodingModule::ReceiverRobustness robustnessMode,
+      VCMDecodeErrorMode errorMode);
+
   void SetNackSettings(size_t max_nack_list_size,
                        int max_packet_age_to_nack,
                        int max_incomplete_time_ms);