Issue 4625: Lock screen silent mode selection does not enable vibration.

This patch set fixes the issue that the silent mode selection on
the lock screen does not consider the vibration settings. This patch
allows setting the phone on vibrate mode if the vibration settings
is enabled and the user sets the phone on silent on the lock screen.

Change-Id: I84c153d6aa73e1fd6a4377e5983f1804123091f9
Signed-off-by: David Sobreira Marques <dpsmarques@gmail.com>