use Java 7's try with resources to ensure the ObjectOutput gets closed correctly

Author: Jacob Mansfield

app/src/main/java/ie/macinnes/tvheadend/player/HtspDataSource.java

@@ -179,11 +179,11 @@ public void onMuxpkt(@NonNull HtspMessage message) {
     // Misc Internal Methods
     private void serializeMessageToBuffer(@NonNull HtspMessage message) {
         ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
-        ObjectOutput objectOutput = null;
 
         mLock.lock();
-        try {
-            objectOutput = new ObjectOutputStream(outputStream);
+        try (
+                ObjectOutput objectOutput = new ObjectOutputStream(outputStream);
+        ) {
             objectOutput.writeObject(message);
             objectOutput.flush();