Update electron-beta to 2.0.0-beta.3 (#5361)
Update electron-beta to 2.0.0-beta.3 (#5361)


404NetworkError/homebrew-versions,pkq/homebrew-versions,Ngrd/homebrew-versions,rogeriopradoj/homebrew-versions,lantrix/homebrew-versions,404NetworkError/homebrew-versions,mahori/homebrew-versions,caskroom/homebrew-versions,caskroom/homebrew-versions,Ngrd/homebrew-versions,pkq/homebrew-versions,victorpopkov/homebrew-versions,mahori/homebrew-cask-versions,rogeriopradoj/homebrew-versions,lantrix/homebrew-versions,victorpopkov/homebrew-versions