Clear loaders array after they are destroyed.

See change Ia577caecbacb226a3ce525a01a66283efb6ba754 for details.

Change-Id: I9f07eeceaa3829f71008e6f6a38ab849095bd69c
Signed-off-by: Roman Mazur <mazur.roman@gmail.com>
add reply.writeNoException() for quick response

In case of SET_ACTIVITY_CONTROLLER_TRANSACTION, there is no reply transaction.
So makes same to other transactions.

Change-Id: I3b9527682662a12f78cc96b6084904f18178fee7
AudioService: Don't adjust volume when vol-downing to vibrate or silent

Pressing vol-down to vibrate or silent would (previously) still adjust the
stream volume, setting the last audible volume to 0, which is not allowed
for voice-capable devices.  Thus, the last audible volume would reset to
default on reboot if on vibrate/silent or the lowest volume setting.

By not adjusting volume when vol-downing to vibrate or silent on
voice-capable devices, the last audible volume is always preserved across
reboot.