More use of finals in output_ast
More use of finals in output_ast

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MOE_MIGRATED_REVID=136376504

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