Fix Chromium clang plugin warnings

NOTRY=true
BUG=webrtc:163

Review-Url: https://codereview.webrtc.org/2286063005
Cr-Commit-Position: refs/heads/master@{#13955}

webrtc/modules/audio_coding/include/audio_coding_module.h

@@ -64,11 +64,9 @@ class AudioCodingModule {
 
  public:
   struct Config {
-    Config() : id(0), neteq_config(), clock(Clock::GetRealTimeClock()) {
-      // Post-decode VAD is disabled by default in NetEq, however, Audio
-      // Conference Mixer relies on VAD decisions and fails without them.
-      neteq_config.enable_post_decode_vad = true;
-    }
+    Config();
+    Config(const Config&);
+    ~Config();
 
     int id;
     NetEq::Config neteq_config;