Propagate media session id into MediaPlayerAndroid

chrome/browser/media/android/remote/remote_media_player_bridge.cc

 // Copyright 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.
 
 #include "chrome/browser/media/android/remote/remote_media_player_bridge.h"
 
 #include <utility>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
@@ skipping 25 matching lines @@
 void DoNothing(int /*i*/) {}
 }
 
 namespace remote_media {
 
 RemoteMediaPlayerBridge::RemoteMediaPlayerBridge(
     int player_id,
     const std::string& user_agent,
     bool hide_url_log,
     RemoteMediaPlayerManager* manager)
-    : MediaPlayerAndroid(player_id,
-                         manager,
-                         base::Bind(&DoNothing),
-                         manager->GetLocalPlayer(player_id)->frame_url()),
+    : MediaPlayerAndroid(
+          player_id,
+          manager,
+          base::Bind(&DoNothing),
+          manager->GetLocalPlayer(player_id)->frame_url(),
+          // TODO(davve): Media session interaction with remote
+          // playback not defined. Use default session for now.
+          // https://github.com/whatwg/mediasession/issues/123
+          media::kDefaultMediaSessionID),

[whywhat, 2016/03/10 22:34:56]

What does using the default session mean in practice? Would it pause other tabs
and add it to the current tab's session so that all players would be controlled
altogether?
I think to play it safe, the remote element should be part of no session at all
(e.g. kInvalidMediaSessionId), until we figure it out.

[davve, 2016/03/11 13:20:29]

Ok, kInvalidMediaSessionId it is.

       width_(0),
       height_(0),
       hide_url_log_(hide_url_log),
       url_(manager->GetLocalPlayer(player_id)->GetUrl()),
       first_party_for_cookies_(
           manager->GetLocalPlayer(player_id)->GetFirstPartyForCookies()),
       user_agent_(user_agent),
       weak_factory_(this) {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   JNIEnv* env = base::android::AttachCurrentThread();
@@ skipping 409 matching lines @@
   Java_RemoteMediaPlayerBridge_setCookies(
       env, java_bridge_.obj(), ConvertUTF8ToJavaString(env, cookies).obj());
 }
 
 MediaPlayerAndroid* RemoteMediaPlayerBridge::GetLocalPlayer() {
   return static_cast<RemoteMediaPlayerManager*>(manager())->GetLocalPlayer(
       player_id());
 }
 
 }  // namespace remote_media