Add tests for #906.
Add tests for #906.

luffy94608/backbone,JesseQin/backbone,gougouGet/backbone,jashkenas/backbone,gmaclennan/backbone,alekskorolev/lightbones,Krasnyanskiy/backbone,nikolas/backbone,ohbarye/backbone,JesseQin/backbone,pandoraui/backbone,elancom/backbone,embarknow/backbone,wangcan2014/backbone,darrrk/backbone,ThiagoGarciaAlves/backbone,dak/backbone,Bug2014/backbone,maryrosecook/backbone-df,d2s/backbone,tibic/backbone,Krasnyanskiy/backbone,lastjune/backbone,Diwahars/backbone,ywenjinlin/backbone,7213/backbone,aihua/backbone,Diwahars/backbone,jewsroch/backbone,paulfalgout/backbone,Flip120/backbone,dcheepurupalli/backbone,Aplopio/backbone,jmeas/backbone,Akkuma/backbone,platinumazure/backbone,sumyfly/backbone,antoniogarrote/backbone,rjz/boneless,getshuvo/backbone,maryrosecook/backbone-df-2,howtolearntocode/backbone,sunday-star/backbone,vin100bk/backbone,tgriesser/backbone,liudianpeng/backbone,ebsco/backbone,moimikey/backbone,craigmichaelmartin/backbone,vincent1988/backbone,DannyDelott/backbone,braddunbar/backbone,wangcan2014/backbone,d2s/backbone,jewsroch/backbone,ywenjinlin/backbone,au-phiware/backbone,liudianpeng/backbone,wxmfront/backbone,embarknow/backbone,LovelyL25/backbone.js,wangdahoo/backbone,vin100bk/backbone,streamablevideo/backbone,Aplopio/backbone,maryrosecook/backbone-df-2,jridgewell/backbone,anhtholee/backbone,Connectlegendary/backbone,amitpatange88/backbonejs,dillonforrest/backbone-df,leimd/backbone,feychenie/backbone,jordansexton/backboner,edgeware/backbone,LovelyL25/backbone.js,amitpatange88/backbonejs,ThisIsManta/Backbone,gfranko/backbone,tadwhitaker/backbone,zhangdimelody/backbone,dillonforrest/backbone-df,zgl2007dj/backbone,ereddate/backbone,addyosmani/backbone,tibic/backbone,dillonforrest/backbone-df-2,webapp/library,braddunbar/backbone,hugohua/backbone,FishbaitHarry/backbone,elancom/backbone,huanglp47/backbone,Bug2014/backbone,ThisIsManta/Backbone,Khan/backbone,cgvarela/backbone,getshuvo/backbone,cailong1028/backbone,darrrk/backbone,nikolas/backbone,dillonforrest/backbone-df,gmaclennan/backbone,zhangdimelody/backbone,closeio/backbone,nvoron23/backbone,christianqw/backbone,rashmisajjan/backbone,kuychaco/backbone,Sachin-Ganesh/backbone,mrblueblue/backbone,Khan/backbone,udhayam/backbone,npmcomponent/solutionio-backbone,ebsco/backbone,ThiagoGarciaAlves/backbone,heroazure/backbone,zhangwei001/backbone,closeio/backbone,zhangwei001/backbone,honger05/backbone,oss-practice/backbone,vlazzle/ax-todos,sueyeh/backbone,mmolinastudio/backbone,malandrew/backbone,premkumargithub/backbone,GrimDerp/backbone,dillonforrest/backbone-df-2,ppker/backbone,guahanweb/backbone,akre54/backbone,wxmfront/backbone,ohbarye/backbone,ridixcr/backbone,neocotic/hipbone,virtru-components/backbone,GerHobbelt/backbone,dak/backbone,jashkenas/backbone,jmeas/backbone,cgvarela/backbone,nvoron23/backbone,batigoal1980/backbone_example,aihua/backbone,mrblueblue/backbone,wjb12/backbone,lujocom/backbone,webcoding/backbone,edgeware/backbone,batigoal1980/backbone_example,Connectlegendary/backbone,wushuyi/backbone,cailong1028/backbone,dillonforrest/backbone-df-2,jstrimpel/backbone,premkumargithub/backbone,sunday-star/backbone,vlazzle/ax-todos,DannyDelott/backbone,gdi2290/backbone,FormidableLabs/backbone,elma-cao/backbone,udhayam/backbone,feychenie/backbone,huanglp47/backbone,zdespolit/backbone,christianqw/backbone,lujocom/backbone,zhoufan879/backbone,wangdahoo/backbone,maryrosecook/backbone-df,elma-cao/backbone,christianqw/backbone,Khan/backbone,moccen/backbone,youprofit/backbone,tadwhitaker/backbone,howtolearntocode/backbone,guigrpa/backbone,yuhualingfeng/backbone,maryrosecook/backbone-df-2,addyosmani/backbone,wakanpaladin/mybackbone,leimd/backbone,wakanpaladin/mybackbone,Niades/backbone,Flip120/backbone,jasoncbautista/backboneX,jungjung917/backbone,chyeh727/backbone,IsoldaJS/isolda-pubsub,dcheepurupalli/backbone,streamablevideo/backbone,linalu1/backbone,chyeh727/backbone,zhoufan879/backbone,webapp/library,mmolinastudio/backbone,zgl2007dj/backbone,GrimDerp/backbone,componentizr/backbone,yawenl/backbone,kuychaco/backbone,fanhc019/backbone,jungjung917/backbone,Sachin-Ganesh/backbone,fanhc019/backbone,malandrew/backbone,Aplopio/backbone,jridgewell/backbone,sumyfly/backbone,sitexa/backbone,trizko/backbone,vincent1988/backbone,akre54/backbone,GerHobbelt/backbone,7213/backbone,tzkKrbys/backbone,moccen/backbone,youprofit/backbone,linalu1/backbone,guahanweb/backbone,yawenl/backbone,yuhualingfeng/backbone,wjb12/backbone,heroazure/backbone,npmcomponent/solutionio-backbone,ppker/backbone,luffy94608/backbone,moimikey/backbone,trizko/backbone,craigmichaelmartin/backbone,mpapp/backbone,timebackzhou/backbone,ntgn81/backbone,pandoraui/backbone,ntgn81/backbone,IsoldaJS/isolda-models,ereddate/backbone,neocotic/hipbone,sitexa/backbone,amdjs/backbone,sueyeh/backbone,anhtholee/backbone,npmcomponent/jashkenas-backbone,timebackzhou/backbone,FishbaitHarry/backbone,webcoding/backbone,wushuyi/backbone,rashmisajjan/backbone,au-phiware/backbone,megawac/backbone,Niades/backbone,jstrimpel/backbone,gougouGet/backbone,tzkKrbys/backbone,lastjune/backbone,paulfalgout/backbone,alekskorolev/lightbones,honger05/backbone,ridixcr/backbone,maryrosecook/backbone-df,zdespolit/backbone,gitterHQ/backbone,platinumazure/backbone,gfranko/backbone