Android: Fix memory leak for remote MediaStream

talk/app/webrtc/java/jni/jni_helpers.h

 /*
  * libjingle
  * Copyright 2015 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are met:
  *
  *  1. Redistributions of source code must retain the above copyright notice,
  *     this list of conditions and the following disclaimer.
  *  2. Redistributions in binary form must reproduce the above copyright notice,
@@ skipping 90 matching lines @@
 std::string JavaToStdString(JNIEnv* jni, const jstring& j_string);
 
 // Return the (singleton) Java Enum object corresponding to |index|;
 jobject JavaEnumFromIndex(JNIEnv* jni, jclass state_class,
                           const std::string& state_class_name, int index);
 
 jobject NewGlobalRef(JNIEnv* jni, jobject o);
 
 void DeleteGlobalRef(JNIEnv* jni, jobject o);
 
-// Given a jweak reference, allocate a (strong) local reference scoped to the
-// lifetime of this object if the weak reference is still valid, or NULL
-// otherwise.
-class WeakRef {
- public:
-  WeakRef(JNIEnv* jni, jweak ref);
-  ~WeakRef();
-  jobject obj() { return obj_; }
-
- private:
-  JNIEnv* const jni_;
-  jobject const obj_;
-};
-
 // Scope Java local references to the lifetime of this object.  Use in all C++
 // callbacks (i.e. entry points that don't originate in a Java callstack
 // through a "native" method call).
 class ScopedLocalRefFrame {
  public:
   explicit ScopedLocalRefFrame(JNIEnv* jni);
   ~ScopedLocalRefFrame();
 
  private:
   JNIEnv* jni_;
@@ skipping 11 matching lines @@
   T operator*() const {
     return obj_;
   }
  private:
   T obj_;
 };
 
 }  // namespace webrtc_jni
 
 #endif  // TALK_APP_WEBRTC_JAVA_JNI_JNI_HELPERS_H_