Adding Angular and dependent packages for testing

third_party/pkg/angular/test/mock/test_bed_spec.dart

+library angular.mock.test_bed_spec;
+
+import '../_specs.dart';
+
+main() =>
+describe('test bed', () {
+  TestBed _;
+  Compiler $compile;
+  Injector injector;
+  Scope $rootScope;
+
+  beforeEach(module((Module module) {
+    module..type(MyTestBedDirective);
+    return (TestBed tb) => _ = tb;
+  }));
+
+  it('should allow for a scope-based compile', () {
+
+    inject((Scope scope) {
+      Scope childScope = scope.$new();
+
+      var element = $('<div my-directive probe="i"></div>');
+      _.compile(element, scope: childScope);
+
+      Probe probe = _.rootScope.i;
+      var directiveInst = probe.directive(MyTestBedDirective);
+
+      childScope.$destroy();
+
+      expect(directiveInst.destroyed).toBe(true);
+    });
+  });
+
+});
+
+@NgDirective(selector: '[my-directive]')
+class MyTestBedDirective {
+  bool destroyed = false;
+
+  MyTestBedDirective(Scope scope) {
+    scope.$on(r'$destroy', () {
+      destroyed = true;
+    });
+  }
+}