fix(core): remove NgZone_ and use NgZone instead

modules/angular2/test/core/render/dom/events/event_manager_spec.ts

@@ -14,7 +14,7 @@ import {
   EventManagerPlugin,
   DomEventsPlugin
 } from 'angular2/src/core/render/dom/events/event_manager';
-import {NgZone, NgZone_} from 'angular2/src/core/zone/ng_zone';
+import {NgZone} from 'angular2/src/core/zone/ng_zone';
 import {ListWrapper, Map, MapWrapper} from 'angular2/src/core/facade/collection';
 import {DOM} from 'angular2/src/core/dom/dom_adapter';
 
@@ -106,7 +106,7 @@ class FakeEventManagerPlugin extends EventManagerPlugin {
   }
 }
 
-class FakeNgZone extends NgZone_ {
+class FakeNgZone extends NgZone {
   constructor() { super({enableLongStackTrace: false}); }
   run(fn) { fn(); }
 

modules/angular2/test/core/testability/testability_spec.ts

@@ -12,7 +12,7 @@ import {
   SpyObject
 } from 'angular2/test_lib';
 import {Testability} from 'angular2/src/core/testability/testability';
-import {NgZone, NgZone_} from 'angular2/src/core/zone/ng_zone';
+import {NgZone} from 'angular2/src/core/zone/ng_zone';
 import {normalizeBlank} from 'angular2/src/core/facade/lang';
 import {PromiseWrapper} from 'angular2/src/core/facade/async';
 
@@ -21,7 +21,7 @@ function microTask(fn: Function): void {
   PromiseWrapper.resolve(null).then((_) => { fn(); });
 }
 
-class MockNgZone extends NgZone_ {
+class MockNgZone extends NgZone {
   _onTurnStart: () => void;
   _onEventDone: () => void;
 

modules/angular2/test/core/zone/ng_zone_spec.ts

@@ -17,7 +17,7 @@ import {
 import {PromiseCompleter, PromiseWrapper, TimerWrapper} from 'angular2/src/core/facade/async';
 import {BaseException} from 'angular2/src/core/facade/exceptions';
 
-import {NgZone, NgZone_} from 'angular2/src/core/zone/ng_zone';
+import {NgZone} from 'angular2/src/core/zone/ng_zone';
 
 var needsLongerTimers = browserDetection.isSlow || browserDetection.isEdge;
 var resultTimer = 1000;
@@ -47,7 +47,7 @@ export function main() {
   describe("NgZone", () => {
 
     function createZone(enableLongStackTrace) {
-      var zone = new NgZone_({enableLongStackTrace: enableLongStackTrace});
+      var zone = new NgZone({enableLongStackTrace: enableLongStackTrace});
       zone.overrideOnTurnStart(_log.fn('onTurnStart'));
       zone.overrideOnTurnDone(_log.fn('onTurnDone'));
       return zone;