Add "product_available" to product available modules am: 8b6fee83e3 am: 9515ce7a8f am: 581c91dc40 am: fd300ee7b0

Original change: https://android-review.googlesource.com/c/platform/external/libcxx/+/1495836

Change-Id: I85b49a18f3976d76b8594a84dc02f97f3b9c3174