Fix Formula.installed?
Fix Formula.installed?

konqui/brew,alyssais/brew,mahori/brew,Linuxbrew/brew,gregory-nisbet/brew,ilovezfs/brew,claui/brew,pseudocody/brew,vitorgalvao/brew,AnastasiaSulyagina/brew,bfontaine/brew,mistydemeo/homebrew,muellermartin/dist,palxex/brew,EricFromCanada/brew,jmsundar/brew,JCount/brew,pseudocody/brew,pseudocody/brew,reelsense/brew,DomT4/brew,mistydemeo/homebrew,Linuxbrew/brew,MikeMcQuaid/brew,JCount/brew,Homebrew/brew,gordonmcshane/homebrew,konqui/brew,nandub/brew,nandub/brew,DomT4/brew,gordonmcshane/homebrew,bfontaine/brew,amar-laksh/brew_sudo,rwhogg/brew,alyssais/brew,palxex/brew,reelsense/brew,vitorgalvao/brew,tonyg/homebrew,reitermarkus/brew,ilovezfs/brew,mahori/brew,Linuxbrew/brew,jmsundar/brew,MikeMcQuaid/brew,hanxue/linuxbrew,vitorgalvao/brew,sjackman/homebrew,mgrimes/brew,tonyg/homebrew,bfontaine/brew,AnastasiaSulyagina/brew,amar-laksh/brew_sudo,muellermartin/dist,maxim-belkin/brew,Homebrew/brew,gregory-nisbet/brew,Homebrew/brew,maxim-belkin/brew,EricFromCanada/brew,claui/brew,reitermarkus/brew,zmwangx/brew,tonyg/homebrew,sjackman/homebrew,MikeMcQuaid/brew,zmwangx/brew,claui/brew,alyssais/brew,mgrimes/brew,palxex/brew,rwhogg/brew,staticfloat/brew,reitermarkus/brew,sjackman/homebrew,reitermarkus/brew,Linuxbrew/brew,hanxue/linuxbrew,toonetown/homebrew,AnastasiaSulyagina/brew,jmsundar/brew,muellermartin/dist,EricFromCanada/brew,konqui/brew,mistydemeo/homebrew,vitorgalvao/brew,aw1621107/brew,amar-laksh/brew_sudo,ilovezfs/brew,maxim-belkin/brew,staticfloat/brew,mahori/brew,aw1621107/brew,gregory-nisbet/brew,staticfloat/brew,toonetown/homebrew,MikeMcQuaid/brew,nandub/brew,JCount/brew,rwhogg/brew,JCount/brew,gordonmcshane/homebrew,DomT4/brew,sjackman/homebrew,DomT4/brew,nandub/brew,mahori/brew,Homebrew/brew,claui/brew,zmwangx/brew,toonetown/homebrew,mgrimes/brew,EricFromCanada/brew,konqui/brew,hanxue/linuxbrew,aw1621107/brew,reelsense/brew