Merge "Add missing <functional> include" into main am: f0d8f21f2f am: 15c9679cd6 am: 9bbbb0d784

Original change: https://android-review.googlesource.com/c/platform/hardware/google/camera/+/2769121

Change-Id: I4c3add40de96a46cae982d6e0319a2bdc8a798d8
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>