Update sysprop_library API txt am: 419b49ade3 am: cd68e11de7 am: 7aff9ded94

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/1460965

Change-Id: I1cb4d6b3b036a949c70fda5937ae2ac6f65a2f07