VmLauncherApp: Small fix for writing \0 in the end of clipboard text

Bug: 353121151
Test: Interaction with ferrochrome
Change-Id: Ibd9b873c72e706e2db11475c4cce140e8fd0ce77
diff --git a/vmlauncher_app/java/com/android/virtualization/vmlauncher/MainActivity.java b/vmlauncher_app/java/com/android/virtualization/vmlauncher/MainActivity.java
index c2b1fa8..bbf4e4f 100644
--- a/vmlauncher_app/java/com/android/virtualization/vmlauncher/MainActivity.java
+++ b/vmlauncher_app/java/com/android/virtualization/vmlauncher/MainActivity.java
@@ -553,6 +553,7 @@
         try (OutputStream stream = new AutoCloseOutputStream(pfd)) {
             stream.write(header);
             stream.write(text.getBytes());
+            stream.write('\0');
             stream.flush();
             Log.d(TAG, "successfully wrote clipboard data to the VM");
             return true;