chore: remove obsolete files (#10240)

modules/@angular/core/src/change_detection/pipe_transform.dart

@@ -1,33 +0,0 @@
-/**
- * To create a Pipe, you must implement this interface.
- *
- * Angular invokes the `transform` method with the value of a binding
- * as the first argument, and any parameters as the second argument in list form.
- *
- * ## Syntax
- *
- * `value | pipeName[:arg0[:arg1...]]`
- *
- * ### Example ([live demo](http://plnkr.co/edit/f5oyIked9M2cKzvZNKHV?p=preview))
- *
- * The `RepeatPipe` below repeats the value as many times as indicated by the first argument:
- *
- * ```
- * import {Pipe, PipeTransform} from 'angular2/core';
- *
- * @Pipe({name: 'repeat'})
- * export class RepeatPipe implements PipeTransform {
- *   transform(value: any, times: number) {
- *     return value.repeat(times);
- *   }
- * }
- * ```
- *
- * Invoking `{{ 'ok' | repeat:3 }}` in a template produces `okokok`.
- *
- */
-abstract class PipeTransform {
-  // Note: Dart does not support varargs,
-  // so we can't type the `transform` method...
-  // dynamic transform(dynamic value, List<dynamic> ...args): any;
-}