Make GetApplicationContext return a JavaRef.

media/base/android/media_player_android.h

 // Copyright (c) 2013 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 MEDIA_BASE_ANDROID_MEDIA_PLAYER_ANDROID_H_
 #define MEDIA_BASE_ANDROID_MEDIA_PLAYER_ANDROID_H_
 
 #include <jni.h>
 
 #include <memory>
 #include <string>
 
+#include "base/android/scoped_java_ref.h"
 #include "base/callback.h"
 #include "base/macros.h"
 #include "base/memory/weak_ptr.h"
 #include "base/time/time.h"
 #include "media/base/android/media_player_listener.h"
 #include "media/base/media_export.h"
 #include "ui/gfx/geometry/size.h"
 #include "ui/gl/android/scoped_java_surface.h"
 #include "url/gurl.h"
 
@@ skipping 98 matching lines @@
 
   int player_id() { return player_id_; }
 
   GURL frame_url() { return frame_url_; }
 
   int media_session_id() { return media_session_id_; }
 
   // Attach/Detaches |listener_| for listening to all the media events. If
   // |j_media_player| is NULL, |listener_| only listens to the system media
   // events. Otherwise, it also listens to the events from |j_media_player|.
-  void AttachListener(jobject j_media_player);
+  void AttachListener(const base::android::JavaRef<jobject>& j_media_player);
   void DetachListener();
 
  protected:
   MediaPlayerAndroid(
       int player_id,
       MediaPlayerManager* manager,
       const OnDecoderResourcesReleasedCB& on_decoder_resources_released_cb,
       const GURL& frame_url,
       int media_session_id);
 
@@ skipping 55 matching lines @@
   // Weak pointer passed to |listener_| for callbacks.
   // NOTE: Weak pointers must be invalidated before all other member variables.
   base::WeakPtrFactory<MediaPlayerAndroid> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaPlayerAndroid);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_ANDROID_MEDIA_PLAYER_ANDROID_H_