Bug 1290075: Always Init() the VoiceEngine when enumerating audio inputs r=jib

dom/media/webrtc/MediaEngineWebRTC.cpp

@@ -108,7 +108,6 @@ MediaEngineWebRTC::MediaEngineWebRTC(MediaEnginePrefs &aPrefs)
   : mMutex("mozilla::MediaEngineWebRTC"),
     mVoiceEngine(nullptr),
     mAudioInput(nullptr),
-    mAudioEngineInit(false),
     mFullDuplex(aPrefs.mFullDuplex),
     mExtendedFilter(aPrefs.mExtendedFilter),
     mDelayAgnostic(aPrefs.mDelayAgnostic)
@@ -349,11 +348,12 @@ MediaEngineWebRTC::EnumerateAudioDevices(dom::MediaSourceEnum aMediaSource,
     return;
   }
 
-  if (!mAudioEngineInit) {
-    if (ptrVoEBase->Init() < 0) {
-      return;
-    }
-    mAudioEngineInit = true;
+  // Always re-init the voice engine, since if we close the last use we
+  // DeInitEngine() and Terminate(), which shuts down Process() - but means
+  // we have to Init() again before using it.  Init() when already inited is
+  // just a no-op, so call always.
+  if (ptrVoEBase->Init() < 0) {
+    return;
   }
 
   if (!mAudioInput) {

dom/media/webrtc/MediaEngineWebRTC.h

@@ -599,7 +599,6 @@ private:
   webrtc::VoiceEngine* mVoiceEngine;
   webrtc::Config mConfig;
   RefPtr<mozilla::AudioInput> mAudioInput;
-  bool mAudioEngineInit;
   bool mFullDuplex;
   bool mExtendedFilter;
   bool mDelayAgnostic;