fix(Compiler): NPE in parseFlags(). Oops.
fix(Compiler): NPE in parseFlags(). Oops.

PiperOrigin-RevId: 168458110

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