Added a level controller initialization value to MediaConstraints.

webrtc/api/mediaconstraintsinterface.h

Index: webrtc/api/mediaconstraintsinterface.h
diff --git a/webrtc/api/mediaconstraintsinterface.h b/webrtc/api/mediaconstraintsinterface.h
index d6fd6beb9531adf15829bc20ccc405bde88d0062..fbb19551e1c524c6aba8c4f39517cf4541793f52 100644
--- a/webrtc/api/mediaconstraintsinterface.h
+++ b/webrtc/api/mediaconstraintsinterface.h
@@ -75,6 +75,8 @@ class MediaConstraintsInterface {
   static const char kExperimentalNoiseSuppression[];  // googNoiseSuppression2
   static const char kIntelligibilityEnhancer[];  // intelligibilityEnhancer
   static const char kLevelControl[];             // levelControl
+  static const char
+      kLevelControlInitialPeakLevelDBFS[];  // levelControlInitialPeakLevelDBFS

[aleloi, 2016/10/17 14:11:09]

I wonder how the deprecation of media constraints (see
https://bugs.chromium.org/p/webrtc/issues/detail?id=5617) relates to this. I
think it's still currently the right approach, because 
webrtc/api/android/jni/peerconnection_jni.cc seems to only support creating peer
connections with media constraints.

   static const char kHighpassFilter[];  // googHighpassFilter
   static const char kTypingNoiseDetection[];  // googTypingNoiseDetection
   static const char kAudioMirroring[];  // googAudioMirroring