Remove kSkipFrame usage.

webrtc/modules/video_coding/main/source/encoded_frame.cc

Index: webrtc/modules/video_coding/main/source/encoded_frame.cc
diff --git a/webrtc/modules/video_coding/main/source/encoded_frame.cc b/webrtc/modules/video_coding/main/source/encoded_frame.cc
index 0fa44250d7e92055cb864f5bd3268a409a3bcd3a..646dae32ed09eb14af7c30c2a2b2593a505d242d 100644
--- a/webrtc/modules/video_coding/main/source/encoded_frame.cc
+++ b/webrtc/modules/video_coding/main/source/encoded_frame.cc
@@ -233,11 +233,9 @@ webrtc::FrameType VCMEncodedFrame::ConvertFrameType(VideoFrameType frameType)
       return  kVideoFrameKey;
     case kDeltaFrame:
       return kVideoFrameDelta;
-    case kSkipFrame:
-      return kFrameEmpty;
-    default:
-      return kVideoFrameDelta;
   }
+  // Bogus default return value.
+  return kVideoFrameDelta;
 }
 
 VideoFrameType VCMEncodedFrame::ConvertFrameType(webrtc::FrameType frame_type) {