Make CodecType conversion functions non-optional.

webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc

Index: webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
diff --git a/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc b/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
index 2bc74a7e724578392b6bf4f544bdc2c1c76da0dd..c92eb542d57ba8a9360ac457b6fdf5ed9f137435 100644
--- a/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
+++ b/webrtc/media/engine/videoencodersoftwarefallbackwrapper.cc
@@ -26,8 +26,7 @@ bool EnableForcedFallback(const cricket::VideoCodec& codec) {
   if (!webrtc::field_trial::IsEnabled(kVp8ForceFallbackEncoderFieldTrial))
     return false;
 
-  return (PayloadNameToCodecType(codec.name).value_or(kVideoCodecUnknown) ==
-          kVideoCodecVP8);
+  return (PayloadStringToCodecType(codec.name) == kVideoCodecVP8);
 }
 
 bool IsForcedFallbackPossible(const VideoCodec& codec_settings) {