Settings: Update Japanese translation

Change-Id: I82b96144bb47f6367b0068b130089afb7d85d508
Signed-off-by: rdgate <rdgate@gmail.com>
Rename DarkUI icon

Currently themes that include Slim's icon are theming our toggle. This will
allow our toggle to remain and themers to theme it.

Change-Id: I60e5ce97e8dce51aa545b5bea1bac2cc8e72fd7e
Merge "Settings: Update Japanese translation" into jb-mr1
Merge remote-tracking branch 'upstream/jb-mr1' into jb-mr1