Battery style: fix dynamic percentage setting

not being disabled after escaping from the statusbar
settings page and going back to it
(bug reported here: http://review.cyanogenmod.org/#/c/82420/)

PS2: better int name thanks to Michael

Change-Id: I3ddf69081866f6214c8880b6a4e2bab6fcd01b9c

Patchset: 3
http://review.cyanogenmod.org/#/c/83103/