Merge "fastboot: Add header that declares std::function" am: 1f876a81 am:...

Merge "fastboot: Add header that declares std::function" am: 1f876a81 am: 6f18eddc am: 04147b86

Original change: https://android-review.googlesource.com/c/platform/system/core/+/2620235



Change-Id: I36212493a15591965236848cb46510800946ff4a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>