message: docs(core): add documentation for HostListener
  add return value documentations for HostListener callbacks
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  PR Close
diff: @@ -823,6 +823,11 @@ export interface HostListenerDecorator {
  /**
  * Decorator that declares a DOM event to listen for,
  * and provides a handler method to run when that event occurs.
  + *
  + * Angular invokes the supplied handler method when the host element emits the specified event,
  + * and updates the bound element with the result.
  + *
  + * If the handler method returns false, applies `preventDefault` on the bound element.
  */
  (eventName: string, args?: string[]): any;
  new(eventName: string, args?: string[]): any;
  