Merge "Hdmi CEC Mock : Clear the existing callback when new callback is set"...

Merge "Hdmi CEC Mock : Clear the existing callback when new callback is set" into main am: ad148cc9

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2968206



Change-Id: Id150740e5f81a83f94af27d8913dcab3c27b5642
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>