ACM/NetEq: Restructure how post-decode VAD is enabled

webrtc/modules/audio_coding/neteq/include/neteq.h

Index: webrtc/modules/audio_coding/neteq/include/neteq.h
diff --git a/webrtc/modules/audio_coding/neteq/include/neteq.h b/webrtc/modules/audio_coding/neteq/include/neteq.h
index 4067ba5c71fefa63b60827c69330aa54f7ba98f0..72139acbe5ac1cb624c8f7bc0f2329b8e7bb5116 100644
--- a/webrtc/modules/audio_coding/neteq/include/neteq.h
+++ b/webrtc/modules/audio_coding/neteq/include/neteq.h
@@ -81,6 +81,7 @@ class NetEq {
     Config()
         : sample_rate_hz(16000),
           enable_audio_classifier(false),
+          enable_post_decode_vad(false),
           max_packets_in_buffer(50),
           // |max_delay_ms| has the same effect as calling SetMaximumDelay().
           max_delay_ms(2000),
@@ -92,6 +93,7 @@ class NetEq {
 
     int sample_rate_hz;  // Initial value. Will change with input data.
     bool enable_audio_classifier;
+    bool enable_post_decode_vad;
     size_t max_packets_in_buffer;
     int max_delay_ms;
     BackgroundNoiseMode background_noise_mode;