anchor.diff:  
   @Directive(
     selector: '[emitter]',
  -  // TODO(b/71710685): Change to `Visibility.local` to reduce code size.
  -  visibility: Visibility.all,
   )
   class DirectiveEmittingEvent {
     String msg = '';
  
positive.code: @Component(
    selector: 'mycomp-child',
    template: '<div>{{prop1}}</div>',
    // TODO(b/71710685): Change to `Visibility.local` to reduce code size.
    visibility: Visibility.all,
  )
  class MyCompChild {
    String prop1 = 'defaultProp1';
  
negative.code: }
  
  @Directive(
    selector: '[listener]',
    host: const {'(event)': 'onEvent(\$event)'},
  )
  class DirectiveListeningEvent {
    String msg = '';
  