Add post_update.sh

* copy android/*

Test: tools/external_updater/updater.sh update rust/crates/libsqlite3-sys
Test: mm in external/rust/crates/libsqlite3-sys
Change-Id: I2accbf31841648a16180d5732f2d30b61b8d831d
diff --git a/post_update.sh b/post_update.sh
new file mode 100755
index 0000000..52614aa
--- /dev/null
+++ b/post_update.sh
@@ -0,0 +1,9 @@
+#!/bin/bash
+
+# $1 Path to the new version.
+# $2 Path to the old version.
+
+set -x
+set -e
+
+cp -a -n -r $2/android $1/