Bug 918372 - Allocate a single GlobalRef for the Android Context. r=blassey

content/media/webrtc/MediaEngineWebRTC.cpp

@@ -94,15 +94,10 @@ MediaEngineWebRTC::EnumerateVideoDevices(nsTArray<nsRefPtr<MediaEngineVideoSourc
   // get the JVM
   JavaVM *jvm = mozilla::AndroidBridge::Bridge()->GetVM();
 
-  JNIEnv *env;
-  jint res = jvm->AttachCurrentThread(&env, NULL);
-
   if (webrtc::VideoEngine::SetAndroidObjects(jvm, (void*)context) != 0) {
     LOG(("VieCapture:SetAndroidObjects Failed"));
     return;
   }
-
-  env->DeleteGlobalRef(context);
 #endif
 
   if (!mVideoEngine) {

media/webrtc/signaling/src/media-conduit/AudioConduit.cpp

@@ -145,19 +145,10 @@ MediaConduitErrorCode WebrtcAudioConduit::Init(WebrtcAudioConduit *other)
       // get the JVM
       JavaVM *jvm = jsjni_GetVM();
 
-      JNIEnv* env;
-      if (jvm->GetEnv((void**)&env, JNI_VERSION_1_4) != JNI_OK) {
-        CSFLogError(logTag,  "%s: could not get Java environment", __FUNCTION__);
-        return kMediaConduitSessionNotInited;
-      }
-      jvm->AttachCurrentThread(&env, NULL);
-
       if (webrtc::VoiceEngine::SetAndroidObjects(jvm, (void*)context) != 0) {
         CSFLogError(logTag, "%s Unable to set Android objects", __FUNCTION__);
         return kMediaConduitSessionNotInited;
       }
-
-      env->DeleteGlobalRef(context);
 #endif
 
     //Per WebRTC APIs below function calls return NULL on failure

media/webrtc/signaling/src/media-conduit/VideoConduit.cpp

@@ -113,19 +113,10 @@ MediaConduitErrorCode WebrtcVideoConduit::Init()
   // get the JVM
   JavaVM *jvm = jsjni_GetVM();
 
-  JNIEnv* env;
-  if (jvm->GetEnv((void**)&env, JNI_VERSION_1_4) != JNI_OK) {
-      CSFLogError(logTag,  "%s: could not get Java environment", __FUNCTION__);
-      return kMediaConduitSessionNotInited;
-  }
-  jvm->AttachCurrentThread(&env, nullptr);
-
   if (webrtc::VideoEngine::SetAndroidObjects(jvm, (void*)context) != 0) {
     CSFLogError(logTag,  "%s: could not set Android objects", __FUNCTION__);
     return kMediaConduitSessionNotInited;
   }
-
-  env->DeleteGlobalRef(context);
 #endif
 
   if( !(mVideoEngine = webrtc::VideoEngine::Create()) )

widget/android/AndroidBridge.cpp

@@ -49,6 +49,7 @@ NS_IMPL_ISUPPORTS0(nsFilePickerCallback)
 
 StaticRefPtr<AndroidBridge> AndroidBridge::sBridge;
 static unsigned sJavaEnvThreadIndex = 0;
+static jobject sGlobalContext = nullptr;
 static void JavaThreadDetachFunc(void *arg);
 
 // This is a dummy class that can be used in the template for android::sp
@@ -1434,18 +1435,40 @@ AndroidBridge::LockWindow(void *window, unsigned char **bits, int *width, int *h
 
 jobject
 AndroidBridge::GetGlobalContextRef() {
-    JNIEnv *env = GetJNIForThread();
-    if (!env)
-        return 0;
+    if (sGlobalContext == nullptr) {
+        JNIEnv *env = GetJNIForThread();
+        if (!env)
+            return 0;
 
-    AutoLocalJNIFrame jniFrame(env, 2);
+        AutoLocalJNIFrame jniFrame(env, 4);
 
-    jobject context = GetContext();
+        jobject context = GetContext();
+        if (!context) {
+            ALOG_BRIDGE("%s: Could not GetContext()", __FUNCTION__);
+            return 0;
+        }
+        jclass contextClass = env->FindClass("android/content/Context");
+        if (!contextClass) {
+            ALOG_BRIDGE("%s: Could not find Context class.", __FUNCTION__);
+            return 0;
+        }
+        jmethodID mid = env->GetMethodID(contextClass, "getApplicationContext",
+                                         "()Landroid/content/Context;");
+        if (!mid) {
+            ALOG_BRIDGE("%s: Could not find getApplicationContext.", __FUNCTION__);
+            return 0;
+        }
+        jobject appContext = env->CallObjectMethod(context, mid);
+        if (!appContext) {
+            ALOG_BRIDGE("%s: getApplicationContext failed.", __FUNCTION__);
+            return 0;
+        }
 
-    jobject globalRef = env->NewGlobalRef(context);
-    MOZ_ASSERT(globalRef);
+        sGlobalContext = env->NewGlobalRef(appContext);
+        MOZ_ASSERT(sGlobalContext);
+    }
 
-    return globalRef;
+    return sGlobalContext;
 }
 
 bool