Fix for CPSet count increasing even if the same object is added repeatedly.
Fix for CPSet count increasing even if the same object is added repeatedly.

Reviewed by me.

mrcarlberg/cappuccino,enquora/cappuccino,280north/cappuccino,zittix/cappuccino,Rosch/cappuccino,mrcarlberg/cappuccino,daboe01/cappuccino,enquora/cappuccino,rgv151/cappuccino,krodelin/cappuccino,AlexanderMazaletskiy/cappuccino,mrcarlberg/cappuccino,cacaodev/cappuccino,akshell/cappuccino,cacaodev/cappuccino,cappuccino/cappuccino,enquora/cappuccino,kidaa/cappuccino,mrcarlberg/cappuccino,Dogild/cappuccino,deltaprojects/cappuccino,Rosch/cappuccino,dgvivero/CappCoreData,zittix/cappuccino,akshell/cappuccino,FrankReh/cappuccino,primalmotion/cappuccino,dgvivero/CappCoreData,wangshijin/cappuccino,Dogild/cappuccino,primalmotion/cappuccino,kidaa/cappuccino,daboe01/cappuccino,FrankReh/cappuccino,deltaprojects/cappuccino,cappuccino/cappuccino,tancred/cappuccino,AlexanderMazaletskiy/cappuccino,daboe01/cappuccino,rgv151/cappuccino,mrcarlberg/cappuccino,FrankReh/cappuccino,jiangshen/cappuccino,eventualbuddha/cappuccino,AlexanderMazaletskiy/cappuccino,wangshijin/cappuccino,rgv151/cappuccino,cacaodev/cappuccino,primalmotion/cappuccino,mrcarlberg/cappuccino,eventualbuddha/cappuccino,enquora/cappuccino,daboe01/cappuccino,koamac/Cappuccino,tolmasky/cappuccino,dgvivero/CappCoreData,zittix/cappuccino,Dogild/cappuccino,Rosch/cappuccino,280north/cappuccino,wangshijin/cappuccino,krodelin/cappuccino,cacaodev/cappuccino,deltaprojects/cappuccino,Rosch/cappuccino,AlexanderMazaletskiy/cappuccino,deltaprojects/cappuccino,eventualbuddha/cappuccino,kidaa/cappuccino,cappuccino/cappuccino,dgvivero/CappCoreData,rgv151/cappuccino,cappuccino/cappuccino,enquora/cappuccino,FrankReh/cappuccino,Dogild/cappuccino,wangshijin/cappuccino,tolmasky/cappuccino,cappuccino/cappuccino,primalmotion/cappuccino,daboe01/cappuccino,jiangshen/cappuccino,tancred/cappuccino,rgv151/cappuccino,primalmotion/cappuccino,Rosch/cappuccino,tolmasky/cappuccino,akshell/cappuccino,kidaa/cappuccino,Dogild/cappuccino,Rosch/cappuccino,daboe01/cappuccino,krodelin/cappuccino,zittix/cappuccino,kidaa/cappuccino,eventualbuddha/cappuccino,krodelin/cappuccino,tolmasky/cappuccino,280north/cappuccino,tancred/cappuccino,tancred/cappuccino,Dogild/cappuccino,dgvivero/CappCoreData,krodelin/cappuccino,rgv151/cappuccino,kidaa/cappuccino,zittix/cappuccino,tancred/cappuccino,cappuccino/cappuccino,280north/cappuccino,Dogild/cappuccino,tancred/cappuccino,zittix/cappuccino,rgv151/cappuccino,primalmotion/cappuccino,AlexanderMazaletskiy/cappuccino,mrcarlberg/cappuccino,FrankReh/cappuccino,koamac/Cappuccino,deltaprojects/cappuccino,cacaodev/cappuccino,akshell/cappuccino,280north/cappuccino,FrankReh/cappuccino,cacaodev/cappuccino,koamac/Cappuccino,deltaprojects/cappuccino,koamac/Cappuccino,AlexanderMazaletskiy/cappuccino,krodelin/cappuccino,FrankReh/cappuccino,primalmotion/cappuccino,cappuccino/cappuccino,deltaprojects/cappuccino,koamac/Cappuccino,koamac/Cappuccino,cacaodev/cappuccino,FrankReh/cappuccino,daboe01/cappuccino,enquora/cappuccino,krodelin/cappuccino,Rosch/cappuccino,tolmasky/cappuccino,mrcarlberg/cappuccino,enquora/cappuccino,wangshijin/cappuccino,wangshijin/cappuccino,zittix/cappuccino