perf(angular): bundle size improvements for angular (#16966)

angular/src/directives/proxies-utils.ts

@@ -0,0 +1,26 @@
+/* tslint:disable */
+import { fromEvent } from 'rxjs';
+
+export function proxyInputs(Cmp: any, inputs: string[]) {
+  const Prototype = Cmp.prototype;
+  inputs.forEach(item => {
+    Object.defineProperty(Prototype, item, {
+      get() { return this.el[item]; },
+      set(val: any) { this.el[item] = val; },
+    });
+  });
+}
+
+export function proxyMethods(Cmp: any, methods: string[]) {
+  const Prototype = Cmp.prototype;
+  methods.forEach(methodName => {
+    Prototype[methodName] = function() {
+      const args = arguments;
+      return this.el.componentOnReady().then((el: any) => el[methodName].apply(el, args));
+    };
+  });
+}
+
+export function proxyOutputs(instance: any, el: any, events: string[]) {
+  events.forEach(eventName => instance[eventName] = fromEvent(el, eventName));
+}