Fix leaked external surface when several EME videos coexist

chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java

Index: chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java
diff --git a/chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java b/chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java
index d7484028592f1aac1f8f428a057c3c980fac9512..2769be9f44019003aee374162b94b9c984b91cee 100644
--- a/chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java
+++ b/chromecast/browser/android/apk/src/org/chromium/chromecast/shell/ExternalVideoSurfaceContainer.java
@@ -124,9 +124,7 @@ public class ExternalVideoSurfaceContainer implements SurfaceHolder.Callback {
     protected void requestExternalVideoSurface(int playerId) {
         if (mPlayerId == playerId) return;
 
-        if (mPlayerId == INVALID_PLAYER_ID) {
-            setActiveContainer(this);
-        }
+        setActiveContainer(this);
 
         mPlayerId = playerId;
         initializeCurrentPositionOfSurfaceView();
@@ -175,6 +173,7 @@ public class ExternalVideoSurfaceContainer implements SurfaceHolder.Callback {
     }
 
     private void createSurfaceView() {
+        assert mSurfaceView == null;
         mSurfaceView = new NoPunchingSurfaceView(mContentViewCore.getContext());
         mSurfaceView.getHolder().addCallback(this);
         // SurfaceHoder.surfaceCreated() will be called after the SurfaceView is attached to