chore: Remove AngularEntrypoint from TS

Closes #8158

modules/angular2/src/core/angular_entrypoint.dart

@@ -0,0 +1,23 @@
+library angular2.src.core.angular_entrypoint;
+
+/**
+ * Marks a function or method as an Angular 2 entrypoint. Only necessary in Dart code.
+ *
+ * The optional `name` parameter will be reflected in logs when the entry point is processed.
+ *
+ * See [the wiki][] for detailed documentation.
+ * [the wiki]: https://github.com/angular/angular/wiki/Angular-2-Dart-Transformer#entry_points
+ *
+ * ## Example
+ *
+ * ```
+ * @AngularEntrypoint("name-for-debug")
+ * void main() {
+ *   bootstrap(MyComponent);
+ * }
+ * ```
+ */
+class AngularEntrypoint {
+  final String name;
+  const AngularEntrypoint([this.name]);
+}

modules/angular2/src/core/angular_entrypoint.ts

@@ -1,23 +1,3 @@
-import {CONST} from 'angular2/src/facade/lang';
+import 'angular2/src/facade/lang';  // kept so that Tools know this is an ES6 file
 
-/**
- * Marks a function or method as an Angular 2 entrypoint. Only necessary in Dart code.
- *
- * The optional `name` parameter will be reflected in logs when the entry point is processed.
- *
- * See [the wiki][] for detailed documentation.
- * [the wiki]: https://github.com/angular/angular/wiki/Angular-2-Dart-Transformer#entry_points
- *
- * ## Example
- *
- * ```
- * @AngularEntrypoint("name-for-debug")
- * void main() {
- *   bootstrap(MyComponent);
- * }
- * ```
- */
-@CONST()
-export class AngularEntrypoint {
-  constructor(public name?: String) {}
-}
+// TS does not have AngularEntrypoint