Automated checkin: version bump for firefox 25.0b12 release. DONTBUILD CLOSED TREE a=release

--HG--
branch : GECKO250b12_2013102517_RELBRANCH
Added FIREFOX_25_0b12_RELEASE FIREFOX_25_0b12_BUILD1 tag(s) for changeset 8c53a2c86cf4. DONTBUILD CLOSED TREE a=release

--HG--
branch : GECKO250b12_2013102517_RELBRANCH