Fix options page error.
Fix options page error.

"setIcon" should be in the list of messages delivered to the options
page (and for which there is no handler).

VPashkov/vimium,PrestanceDesign/vimium,elegantwww/vimium,PickRelated/vimium,PickRelated/vimium,PickRelated/vimium,Robinson10240/vimium,smblott-github/vimium,smblott-github/vimium,csmalin/vimium,gdh1995/vimium,justalittlenoob/vimium,wildeyes/vimium,elderbas/vimium,justalittlenoob/vimium,tuchangwei/vimium,hhsue/vimium,Lw-Cui/vimium,csmalin/vimium,borgified/vimium,philc/vimium,borgified/vimium,Lw-Cui/vimium,dimatter/vimium,douglas-larocca/vimium,decaffeinate-examples/vimium,dimatter/vimium,philc/vimium,elderbas/vimium,willsALMANJ/vimium,willsALMANJ/vimium,Aleroniponi/vimium,douglas-larocca/vimium,mrmr1993/vimium,Aleroniponi/vimium,poacher2k/vimium,zhangmin510/vimium,bkudria/vimium,VPashkov/vimium,cyrixhero/vimium,cyrixhero/vimium,gdh1995/vimium,Robinson10240/vimium,borgified/vimium,cyrixhero/vimium,dimatter/vimium,PrestanceDesign/vimium,wildeyes/vimium,douglas-larocca/vimium,tuchangwei/vimium,wildeyes/vimium,Lw-Cui/vimium,willsALMANJ/vimium,elegantwww/vimium,PrestanceDesign/vimium,zhangmin510/vimium,philc/vimium,poacher2k/vimium,Aleroniponi/vimium,bkudria/vimium,bkudria/vimium,decaffeinate-examples/vimium,csmalin/vimium,zhangmin510/vimium,VPashkov/vimium,elderbas/vimium,smblott-github/vimium,elegantwww/vimium,poacher2k/vimium,justalittlenoob/vimium,hhsue/vimium,tuchangwei/vimium,mrmr1993/vimium,hhsue/vimium,Robinson10240/vimium,gdh1995/vimium,mrmr1993/vimium,decaffeinate-examples/vimium