jni: Pass method parameters as JavaParamRef in remoting.

remoting/client/jni/jni_client.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_CLIENT_JNI_JNI_CLIENT_H_
 #define REMOTING_CLIENT_JNI_JNI_CLIENT_H_
 
 #include <jni.h>
 
+#include "base/android/scoped_java_ref.h"
 #include "base/macros.h"
 
 namespace remoting {
 
 class JniClient {
  public:
   JniClient();
   ~JniClient();
 
   // Register C++ methods exposed to Java using JNI.
   static bool RegisterJni(JNIEnv* env);
 
-  void Destroy(JNIEnv* env, jobject caller);
+  void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& caller);
 
  private:
   DISALLOW_COPY_AND_ASSIGN(JniClient);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_CLIENT_JNI_JNI_CLIENT_H_