JsonStore: pep8 fix, do not check if boolean is False
JsonStore: pep8 fix, do not check if boolean is False

Do not check if boolean is False, use boolean context instead.
kivy/kivy,kived/kivy,inclement/kivy,jegger/kivy,KeyWeeUsr/kivy,janssen/kivy,bionoid/kivy,KeyWeeUsr/kivy,jkankiewicz/kivy,LogicalDash/kivy,rnixx/kivy,jkankiewicz/kivy,darkopevec/kivy,matham/kivy,manthansharma/kivy,autosportlabs/kivy,tony/kivy,manthansharma/kivy,autosportlabs/kivy,aron-bordin/kivy,LogicalDash/kivy,kived/kivy,inclement/kivy,LogicalDash/kivy,tony/kivy,darkopevec/kivy,bionoid/kivy,jkankiewicz/kivy,darkopevec/kivy,bionoid/kivy,autosportlabs/kivy,inclement/kivy,aron-bordin/kivy,rafalo1333/kivy,LogicalDash/kivy,aron-bordin/kivy,Cheaterman/kivy,akshayaurora/kivy,KeyWeeUsr/kivy,jegger/kivy,janssen/kivy,darkopevec/kivy,rnixx/kivy,matham/kivy,KeyWeeUsr/kivy,janssen/kivy,jegger/kivy,rafalo1333/kivy,matham/kivy,jegger/kivy,kivy/kivy,aron-bordin/kivy,Cheaterman/kivy,rnixx/kivy,akshayaurora/kivy,kived/kivy,bionoid/kivy,akshayaurora/kivy,rafalo1333/kivy,janssen/kivy,tony/kivy,matham/kivy,Cheaterman/kivy,jkankiewicz/kivy,kivy/kivy,manthansharma/kivy,Cheaterman/kivy,manthansharma/kivy