quiethours: do not play screenshot sound

If we are in quiet hours do not play any sound when we take a screenshot.

Change-Id: Ideaa5c11611b7e3c9d6ca4d27e801cd2fb4eadac
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>
Merge remote branch 'cm/cm-11.0' into cm-11.0