Merge "KeyUtil: use static local variable in isFsKeyringSupported()" am: 256b23b1c5 am: 350b5ae900

Original change: https://android-review.googlesource.com/c/platform/system/vold/+/1365220

Change-Id: Ia7fca6e61c58317002271c8338bb01a12e8223a5