fix(life_cycle): throw when recursively reentering LifeCycle.tick

modules/angular2/test/core/life_cycle/life_cycle_spec.ts

@@ -0,0 +1,38 @@
+import {
+  ddescribe,
+  describe,
+  it,
+  iit,
+  xit,
+  expect,
+  beforeEach,
+  afterEach,
+  el,
+  AsyncTestCompleter,
+  fakeAsync,
+  tick,
+  SpyObject,
+  inject,
+  proxy
+  } from 'angular2/test_lib';
+import {LifeCycle} from 'angular2/src/core/life_cycle/life_cycle';
+import {ChangeDetector} from 'angular2/change_detection';
+import {IMPLEMENTS} from 'angular2/src/facade/lang';
+
+@proxy
+@IMPLEMENTS(ChangeDetector)
+class SpyChangeDetector extends SpyObject {
+  constructor() { super(ChangeDetector); }
+  noSuchMethod(m) { return super.noSuchMethod(m) }
+}
+
+export function main() {
+  describe("LifeCycle", () => {
+    it("should throw when reentering tick", () => {
+      var cd = <any>new SpyChangeDetector();
+      var lc = new LifeCycle(null, cd, false);
+      cd.spy("detectChanges").andCallFake(() => lc.tick());
+      expect(() => lc.tick()).toThrowError("LifeCycle.tick is called recursively");
+    });
+  });
+}