Code review comment for lp:~azzar1/unity/lp-1170508

armhf build fails:

/tmp/buildd/unity-7.1.2+14.04.20131106.1bzr3590pkg0trusty0/unity-shared/UnityWindowView.cpp:238:10: error: variable 'temp_background_color' set but not used [-Werror=unused-but-set-variable]
     auto temp_background_color = background_color();