Merge "_GNU_SOURCE is public; _USE_GNU is an implementation detail." into main am: 0b46c906

Original change: https://android-review.googlesource.com/c/platform/frameworks/base/+/3361286



Change-Id: I83daccaaf34502b8da4771e60a4f7b30f2c2f08b
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>