Remove SystemSettingSwitchPreference.

We should not introduce one-off UI patterns when there are plenty of
examples where the same usage pattern (a feature on its own
PreferenceScreen with a global enable switch in the action bar) is
handled differently everywhere else (e.g. daydream, cast display,
blacklist). This makes for inconsistent UX.
Also, there are discoverability issues: As there's no other case of a
preference with an embedded control widget opening another preference
screen, users won't expect to find another screen behind it.
Additionally - but entirely subjective - the control looks plain ugly,
as the preference padding is too large for the large switch.

Change-Id: I61284e961babefa3748102b05055fb1d03b079b0
Hide heads up settings and show a notice if heads up is disabled.

This follows a UI pattern used at several other places, such as
daydream, screencast, profiles or blacklist settings.

Change-Id: I5635338ceccae8ba8450284d3078889333fb77c6
Settings: Add heads up quicksettings tile. (2/2)

Change-Id: Ib1db69671d9f5c2c6dfa019739674fee50df9340
Settings: Fix switch state being out of sync.

    - Since QS Tile can also set state of Heads up now,
    we have to set a content observer for the action bar
    switch.

Change-Id: I1c63fd2627a0f823eb6982456e1ed79ab84d1957
Automatic translation import

Change-Id: Icb77a2c1f07d2e54f64928f32f0b16482772fe47
Add some system packages to package list adapter.

As we're using the adapter for notification control stuff, we need to
include those packages, too, as they're throwing notifications as well.

Also optimize code a little.

Change-Id: I8829041a535923e3d93d9566e27eb99c48f25abd
Merge remote-tracking branch 'upstream/cm-11.0' into cm-11.0

Conflicts:
	src/com/android/settings/cyanogenmod/NotificationDrawer.java