Notify the WebView that its customView is not being displayed instead of failing silently.
diff --git a/src/com/android/browser/BrowserActivity.java b/src/com/android/browser/BrowserActivity.java
index d39d897..462e434 100644
--- a/src/com/android/browser/BrowserActivity.java
+++ b/src/com/android/browser/BrowserActivity.java
@@ -2582,8 +2582,11 @@
     }
 
     void onShowCustomView(View view, WebChromeClient.CustomViewCallback callback) {
-        if (mCustomView != null)
+        // if a view already exists then immediately terminate the new one
+        if (mCustomView != null) {
+            callback.onCustomViewHidden();
             return;
+        }
 
         // Add the custom view to its container.
         mCustomViewContainer.addView(view, COVER_SCREEN_GRAVITY_CENTER);