Track a window's class rather than polling it on name changes.
Track a window's class rather than polling it on name changes.

jerluc/wmii,darkfeline/wmii,rvedam/wmii,wingyplus/wmii,rvedam/wmii,Sirikid/wmii,sigmavirus24/wmii,wingyplus/wmii,sigmavirus24/wmii,Sirikid/wmii,jerluc/wmii,sigmavirus24/wmii,rvedam/wmii,darkfeline/wmii,rvedam/wmii,jerluc/wmii,rvedam/wmii,jerluc/wmii,jerluc/wmii,sigmavirus24/wmii,Sirikid/wmii,wingyplus/wmii,wingyplus/wmii,wingyplus/wmii,sigmavirus24/wmii,darkfeline/wmii,Sirikid/wmii,darkfeline/wmii,Sirikid/wmii,darkfeline/wmii