Merge "inputflinger: add missing <functional> include" into main am: 3508150e

Original change: https://android-review.googlesource.com/c/platform/frameworks/native/+/2758333



Change-Id: I932d2b1d79f435769976d7d2916cfb73c51123a4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>