Settings: don't remove navigation bar prefs when toggling

For devices which support the KeyDisabler class, toggling the nav bar
removes the navigation bar category, but does not add it back. If a
device can have the nav bar toggled, don't remove the category, but just
disable/enable it.

Change-Id: Ie527e3eb357e4a46097257d90c07c78e61f043a9
Signed-off-by: Roman Birg <roman@cyngn.com>
Settings: Fix the failing strings

Change-Id: I93865d793eef711f8738e00e843e9d4670724c66
Improve notification spam filter code.

- Follow coding style guidelines
- Replace dialog shown on click by adding the relevant information and
  the delete button to the item itself
- Minor layout tweaks
- Make the empty view more descriptive
- Add license headers

Change-Id: Ic685364087d6a093fdbb6a143a9c6ed78596b62b
Automatic translation import

Change-Id: I174cb4b02fa7fd9730c080d8224b04df53627b50