fix(_tests): Use --verbose flag so that build_runner logs actually show up in travis.
fix(_tests): Use --verbose flag so that build_runner logs actually show up in travis.

PiperOrigin-RevId: 174232057

matanlurey/angular,angulardart/angular,kevmoo/angular,angulardart/angular,angulardart/angular,kevmoo/angular,chalin/angular2,chalin/angular2,matanlurey/angular,chalin/angular2,matanlurey/angular,kevmoo/angular