Adding Angular and dependent packages for testing

third_party/pkg/angular/lib/directive/ng_template.dart

+part of angular.directive;
+
+/**
+ * The [NgTemplateElementDirective] allows one to preload an Angular template
+ * into the [TemplateCache].  It works on `<template>` and `<script>` elements
+ * that have `type="text/ng-template`.  For such elements, The entire contents
+ * of the elements are loaded into the [TemplateCache] under the URL specified
+ * by the `id` attribute.
+ *
+ * Sample usage:
+ *
+ *     <template id="template_1.html" type="text/ng-template">
+ *       TEMPLATE 1 CONTENTS
+ *     </template>
+ *     <script id="template_2.html" type="text/ng-template">
+ *       TEMPLATE 2 CONTENTS
+ *     </template>
+ *
+ * Refer [TemplateCache] for a **full example** as well as more information.
+ */
+@NgDirective(
+  selector: 'template[type=text/ng-template]',
+  map: const {'id': '@templateUrl'})
+@NgDirective(
+  selector: 'script[type=text/ng-template]',
+  children: NgAnnotation.IGNORE_CHILDREN,
+  map: const {'id': '@templateUrl'})
+class NgTemplateDirective {
+  dom.Element element;
+  TemplateCache templateCache;
+
+  NgTemplateDirective(this.element, this.templateCache);
+  set templateUrl(url) => templateCache.put(url, new HttpResponse(200,
+      (element is dom.TemplateElement
+        ? (element as dom.TemplateElement).content.innerHtml
+        : element.innerHtml)));
+}