Propagate media session id into MediaPlayerAndroid

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

Index: chrome/browser/media/android/remote/remote_media_player_bridge.cc
diff --git a/chrome/browser/media/android/remote/remote_media_player_bridge.cc b/chrome/browser/media/android/remote/remote_media_player_bridge.cc
index bcb4dab3453d1985b88eacba41fd007e6ea6eb9e..41d728561c549614892fc5d211996a0a88b066fc 100644
--- a/chrome/browser/media/android/remote/remote_media_player_bridge.cc
+++ b/chrome/browser/media/android/remote/remote_media_player_bridge.cc
@@ -43,10 +43,15 @@ RemoteMediaPlayerBridge::RemoteMediaPlayerBridge(
     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),