CEC: Let <Active Source> from the active source work

<Active Source> from the device which is already in active
source state is being ignored now, but it should work with an effect
of putting input view foreground in case it is hidden behind
home launcher overlay.

For better user experience, this change lets the command from
the active source takes effect to hide the overlay if present.

Bug: 19171319
Change-Id: I43d2646f2ad470b3636e82ff71ac83cf0031ef6c