调整进直播间loading界面与播放器绑定，播放器准备完成后再隐藏。

优化播放器加载速度1

live/src/main/java/com/yunbao/live/utils/LiveExoPlayerManager.java

@@ -106,7 +106,7 @@ public class LiveExoPlayerManager {
                 Log.i(TAG, "onPlaybackStateChanged 1: " + playbackState);
                 if (playbackState == Player.STATE_READY) {
                     player2.stop();
-                    player2.setVideoSurface(null);
+                    player2.clearVideoSurface();
                     player1.play();
                     Log.i(TAG, "切换播放器1");
                     handler.removeCallbacks(buffRunnable);
@@ -159,7 +159,7 @@ public class LiveExoPlayerManager {
                 Log.i(TAG, "onPlaybackStateChanged 2: " + playbackState);
                 if (playbackState == Player.STATE_READY) {
                     player1.stop();
-                    player1.setVideoSurface(null);
+                    player1.clearVideoSurface();
                     player2.play();
                     Log.i(TAG, "切换播放器2 " + player2.isPlaying());
                     handler.removeCallbacks(buffRunnable);