Fix warning under Ruby 2.2
Fix warning under Ruby 2.2

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