Replace RTC_DCHECK(false) with RTC_NOTREACHED().

webrtc/common_audio/vad/vad.cc

Index: webrtc/common_audio/vad/vad.cc
diff --git a/webrtc/common_audio/vad/vad.cc b/webrtc/common_audio/vad/vad.cc
index 77de5166db3be1ebabe964ca89ff1f8fb1d25dcf..e634aa2ffd476511cd98df5d08f8a89125b87a16 100644
--- a/webrtc/common_audio/vad/vad.cc
+++ b/webrtc/common_audio/vad/vad.cc
@@ -37,7 +37,7 @@ class VadImpl final : public Vad {
       case 1:
         return kActive;
       default:
-        RTC_DCHECK(false) << "WebRtcVad_Process returned an error.";
+        RTC_NOTREACHED() << "WebRtcVad_Process returned an error.";
         return kError;
     }
   }