Bug 946865 - Move Load Adaption preference to the main thread. r=jesup

content/media/webrtc/LoadMonitor.cpp

@@ -21,7 +21,6 @@
 #include "mozilla/TimeStamp.h"
 #include "mozilla/Util.h"
 #include "mozilla/Services.h"
-#include "mozilla/Preferences.h"
 
 #if defined(ANDROID) || defined(LINUX) || defined(XP_MACOSX)
 #include <sys/time.h>
@@ -323,10 +322,6 @@ LoadMonitor::GetSystemLoad() {
 nsresult
 LoadMonitor::Init(nsRefPtr<LoadMonitor> &self)
 {
-  if (!Preferences::GetBool("media.navigator.load_adapt", false)) {
-    return NS_OK;
-  }
-
 #if defined(PR_LOGGING)
   if (!gLoadMonitorLog)
     gLoadMonitorLog = PR_NewLogModule("LoadMonitor");

content/media/webrtc/MediaEngine.h

@@ -45,6 +45,7 @@ public:
   static const int DEFAULT_VIDEO_WIDTH = 640;
   static const int DEFAULT_VIDEO_HEIGHT = 480;
   static const int DEFAULT_AUDIO_TIMER_MS = 10;
+  static const bool DEFAULT_LOAD_ADAPT = false;
 
   /* Populate an array of video sources in the nsTArray. Also include devices
    * that are currently unavailable. */
@@ -130,6 +131,7 @@ struct MediaEnginePrefs {
   int32_t mHeight;
   int32_t mFPS;
   int32_t mMinFPS;
+  bool mLoadAdapt;
 };
 
 class MediaEngineVideoSource : public MediaEngineSource

content/media/webrtc/MediaEngineWebRTC.cpp

@@ -43,7 +43,7 @@ GetUserMediaLog()
 
 namespace mozilla {
 #ifndef MOZ_B2G_CAMERA
-MediaEngineWebRTC::MediaEngineWebRTC()
+MediaEngineWebRTC::MediaEngineWebRTC(MediaEnginePrefs &aPrefs)
   : mMutex("mozilla::MediaEngineWebRTC")
   , mVideoEngine(nullptr)
   , mVoiceEngine(nullptr)
@@ -56,8 +56,10 @@ MediaEngineWebRTC::MediaEngineWebRTC()
   if (compMgr) {
     compMgr->IsContractIDRegistered(NS_TABSOURCESERVICE_CONTRACTID, &mHasTabVideoSource);
   }
-  mLoadMonitor = new LoadMonitor();
-  mLoadMonitor->Init(mLoadMonitor);
+  if (aPrefs.mLoadAdapt) {
+      mLoadMonitor = new LoadMonitor();
+      mLoadMonitor->Init(mLoadMonitor);
+  }
 }
 #endif
 
@@ -359,7 +361,8 @@ MediaEngineWebRTC::Shutdown()
   mVideoEngine = nullptr;
   mVoiceEngine = nullptr;
 
-  mLoadMonitor->Shutdown();
+  if (mLoadMonitor)
+    mLoadMonitor->Shutdown();
 }
 
 }

content/media/webrtc/MediaEngineWebRTC.h

@@ -367,7 +367,7 @@ public:
     mLoadMonitor->Init(mLoadMonitor);
   }
 #else
-  MediaEngineWebRTC();
+  MediaEngineWebRTC(MediaEnginePrefs &aPrefs);
 #endif
   ~MediaEngineWebRTC() {
     Shutdown();

dom/media/MediaManager.cpp

@@ -1044,6 +1044,7 @@ MediaManager::MediaManager()
   mPrefs.mHeight = MediaEngine::DEFAULT_VIDEO_HEIGHT;
   mPrefs.mFPS    = MediaEngine::DEFAULT_VIDEO_FPS;
   mPrefs.mMinFPS = MediaEngine::DEFAULT_VIDEO_MIN_FPS;
+  mPrefs.mLoadAdapt = MediaEngine::DEFAULT_LOAD_ADAPT;
 
   nsresult rv;
   nsCOMPtr<nsIPrefService> prefs = do_GetService("@mozilla.org/preferences-service;1", &rv);
@@ -1088,6 +1089,7 @@ MediaManager::Get() {
       prefs->AddObserver("media.navigator.video.default_height", sSingleton, false);
       prefs->AddObserver("media.navigator.video.default_fps", sSingleton, false);
       prefs->AddObserver("media.navigator.video.default_minfps", sSingleton, false);
+      prefs->AddObserver("media.navigator.load_adapt", sSingleton, false);
     }
   }
   return sSingleton;
@@ -1411,7 +1413,7 @@ MediaManager::GetBackend(uint64_t aWindowId)
   if (!mBackend) {
 #if defined(MOZ_WEBRTC)
   #ifndef MOZ_B2G_CAMERA
-    mBackend = new MediaEngineWebRTC();
+    mBackend = new MediaEngineWebRTC(mPrefs);
   #else
     mBackend = new MediaEngineWebRTC(mCameraManager, aWindowId);
   #endif
@@ -1509,6 +1511,18 @@ MediaManager::GetPref(nsIPrefBranch *aBranch, const char *aPref,
   }
 }
 
+void
+MediaManager::GetPrefBool(nsIPrefBranch *aBranch, const char *aPref,
+                          const char *aData, bool *aVal)
+{
+  bool temp;
+  if (aData == nullptr || strcmp(aPref,aData) == 0) {
+    if (NS_SUCCEEDED(aBranch->GetBoolPref(aPref, &temp))) {
+      *aVal = temp;
+    }
+  }
+}
+
 void
 MediaManager::GetPrefs(nsIPrefBranch *aBranch, const char *aData)
 {
@@ -1516,6 +1530,7 @@ MediaManager::GetPrefs(nsIPrefBranch *aBranch, const char *aData)
   GetPref(aBranch, "media.navigator.video.default_height", aData, &mPrefs.mHeight);
   GetPref(aBranch, "media.navigator.video.default_fps", aData, &mPrefs.mFPS);
   GetPref(aBranch, "media.navigator.video.default_minfps", aData, &mPrefs.mMinFPS);
+  GetPrefBool(aBranch, "media.navigator.load_adapt", aData, &mPrefs.mLoadAdapt);
 }
 
 nsresult
@@ -1544,6 +1559,7 @@ MediaManager::Observe(nsISupports* aSubject, const char* aTopic,
       prefs->RemoveObserver("media.navigator.video.default_height", this);
       prefs->RemoveObserver("media.navigator.video.default_fps", this);
       prefs->RemoveObserver("media.navigator.video.default_minfps", this);
+      prefs->RemoveObserver("media.navigator.load_adapt", this);
     }
 
     // Close off any remaining active windows.

dom/media/MediaManager.h

@@ -506,6 +506,8 @@ private:
 
   void GetPref(nsIPrefBranch *aBranch, const char *aPref,
                const char *aData, int32_t *aVal);
+  void GetPrefBool(nsIPrefBranch *aBranch, const char *aPref,
+                   const char *aData, bool *aVal);
   void GetPrefs(nsIPrefBranch *aBranch, const char *aData);
 
   // Make private because we want only one instance of this class