refactor(middleware): update middleware/common to ES6 (#3028)
refactor(middleware): update middleware/common to ES6 (#3028)


johnjbarton/karma,karma-runner/karma,johnjbarton/karma,maksimr/karma,karma-runner/karma,maksimr/karma,johnjbarton/karma,david-garcia-nete/karma,david-garcia-nete/karma,karma-runner/karma,maksimr/karma,karma-runner/karma,david-garcia-nete/karma,johnjbarton/karma