Fix Chromium clang plugin warnings

webrtc/modules/audio_processing/vad/voice_activity_detector.cc

Index: webrtc/modules/audio_processing/vad/voice_activity_detector.cc
diff --git a/webrtc/modules/audio_processing/vad/voice_activity_detector.cc b/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
index fc9d103918251e83e0100f77ffe4a8270b0ec496..7b495f4231fea5f09fba59a842c1c3e3d0267bc6 100644
--- a/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
+++ b/webrtc/modules/audio_processing/vad/voice_activity_detector.cc
@@ -31,6 +31,8 @@ VoiceActivityDetector::VoiceActivityDetector()
       standalone_vad_(StandaloneVad::Create()) {
 }
 
+VoiceActivityDetector::~VoiceActivityDetector() = default;
+
 // Because ISAC has a different chunk length, it updates
 // |chunkwise_voice_probabilities_| and |chunkwise_rms_| when there is new data.
 // Otherwise it clears them.