Remove kVideoCodecUnknown from WebRTC.

There is no difference between how we handle "generic" and "unkown" codecs,
so we don't need to represent both.

Bug: webrtc:8136
Change-Id: I42b0dbc8a0bae67cc21742303c963c8dd5bde1f6
Reviewed-on: https://webrtc-review.googlesource.com/92086
Reviewed-by: Karl Wiberg <kwiberg@webrtc.org>
Reviewed-by: Rasmus Brandt <brandtr@webrtc.org>
Reviewed-by: Niels Moller <nisse@webrtc.org>
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#24316}
diff --git a/modules/video_coding/encoder_database.cc b/modules/video_coding/encoder_database.cc
index 3df0a9d..5a89590 100644
--- a/modules/video_coding/encoder_database.cc
+++ b/modules/video_coding/encoder_database.cc
@@ -44,7 +44,6 @@
   RTC_DCHECK_GE(number_of_cores, 1);
   // Make sure the start bit rate is sane...
   RTC_DCHECK_LE(send_codec->startBitrate, 1000000);
-  RTC_DCHECK(send_codec->codecType != kVideoCodecUnknown);
   bool reset_required = pending_encoder_reset_;
   if (number_of_cores_ != number_of_cores) {
     number_of_cores_ = number_of_cores;
@@ -155,15 +154,8 @@
       }
       break;
 
-    case kVideoCodecGeneric:
+    default:
       break;
-    // Known codecs without payload-specifics
-    case kVideoCodecI420:
-    case kVideoCodecMultiplex:
-      break;
-    // Unknown codec type, reset just to be sure.
-    case kVideoCodecUnknown:
-      return true;
   }
 
   for (unsigned char i = 0; i < new_send_codec.numberOfSimulcastStreams; ++i) {