Make stream_id internal to StreamTextureHost.

content/renderer/media/android/webmediaplayer_android.h

Index: content/renderer/media/android/webmediaplayer_android.h
diff --git a/content/renderer/media/android/webmediaplayer_android.h b/content/renderer/media/android/webmediaplayer_android.h
index 5492bdb056720d91d0ebc751bba965cf85989673..c7af8ce50dfe3613e01f31b04f9a76de528578f2 100644
--- a/content/renderer/media/android/webmediaplayer_android.h
+++ b/content/renderer/media/android/webmediaplayer_android.h
@@ -229,7 +229,6 @@ class WebMediaPlayerAndroid
   void UpdateNetworkState(blink::WebMediaPlayer::NetworkState state);
   void UpdateReadyState(blink::WebMediaPlayer::ReadyState state);
   void TryCreateStreamTextureProxyIfNeeded();
-  void DoCreateStreamTexture();
 
   // Helper method to reestablish the surface texture peer for android
   // media player.
@@ -348,9 +347,6 @@ class WebMediaPlayerAndroid
   // point for when the mailbox was produced.
   gpu::Mailbox texture_mailbox_;
 
-  // Stream texture ID allocated to the video.
-  unsigned int stream_id_;
-
   // Whether the media player has been initialized.
   bool is_player_initialized_;