fix(zone.js): remove unused Promise overwritten setter logic (#36851)

In the early Zone.js versions (< 0.10.3), `ZoneAwarePromise` did not support `Symbol.species`,
so when user used a 3rd party `Promise` such as `es6-promise`, and try to load the promise library after import of `zone.js`, the loading promise library will overwrite the patched `Promise` from `zone.js` and will break `Promise` semantics with respect to `zone.js`.

Starting with `zone.js` 0.10.3, `Symbol.species` is supported therefore this will not longer be an issue. (https://github.com//pull/34533)

Before 0.10.3, the logic in zone.js tried to handle the case in the wrong way. It did so by overriding the descriptor of `global.Promise`, to allow the 3rd party libraries to override native `Promise` instead of `ZoneAwarePromise`. This is not the correct solution, and since the `Promise.species` is now supported, the 3rd party solution of overriding `global.Promise` is no longer needed.

PR removes the wrong work around logic. (This will improve the bundle size.)

PR Close #36851

goldens/size-tracking/integration-payloads.json

@@ -3,8 +3,8 @@
     "master": {
       "uncompressed": {
         "runtime-es2015": 1485,
-        "main-es2015": 141394,
+        "main-es2015": 141151,
-        "polyfills-es2015": 36963
+        "polyfills-es2015": 36571
       }
     }
   },
@@ -22,7 +22,7 @@
       "uncompressed": {
         "runtime-es2015": 1485,
         "main-es2015": 147314,
-        "polyfills-es2015": 36963
+        "polyfills-es2015": 36571
       }
     }
   },

packages/zone.js/lib/common/promise.ts

@@ -459,44 +459,6 @@ Zone.__load_patch('ZoneAwarePromise', (global: any, Zone: ZoneType, api: _ZonePr
   ZoneAwarePromise['all'] = ZoneAwarePromise.all;
 
   const NativePromise = global[symbolPromise] = global['Promise'];
-  const ZONE_AWARE_PROMISE = Zone.__symbol__('ZoneAwarePromise');
-
-  let desc = ObjectGetOwnPropertyDescriptor(global, 'Promise');
-  if (!desc || desc.configurable) {
-    desc && delete desc.writable;
-    desc && delete desc.value;
-    if (!desc) {
-      desc = {configurable: true, enumerable: true};
-    }
-    desc.get = function() {
-      // if we already set ZoneAwarePromise, use patched one
-      // otherwise return native one.
-      return global[ZONE_AWARE_PROMISE] ? global[ZONE_AWARE_PROMISE] : global[symbolPromise];
-    };
-    desc.set = function(NewNativePromise) {
-      if (NewNativePromise === ZoneAwarePromise) {
-        // if the NewNativePromise is ZoneAwarePromise
-        // save to global
-        global[ZONE_AWARE_PROMISE] = NewNativePromise;
-      } else {
-        // if the NewNativePromise is not ZoneAwarePromise
-        // for example: after load zone.js, some library just
-        // set es6-promise to global, if we set it to global
-        // directly, assertZonePatched will fail and angular
-        // will not loaded, so we just set the NewNativePromise
-        // to global[symbolPromise], so the result is just like
-        // we load ES6 Promise before zone.js
-        global[symbolPromise] = NewNativePromise;
-        if (!NewNativePromise.prototype[symbolThen]) {
-          patchThen(NewNativePromise);
-        }
-        api.setNativePromise(NewNativePromise);
-      }
-    };
-
-    ObjectDefineProperty(global, 'Promise', desc);
-  }
-
   global['Promise'] = ZoneAwarePromise;
 
   const symbolThenPatched = __symbol__('thenPatched');

packages/zone.js/lib/extra/bluebird.ts

@@ -80,6 +80,6 @@ Zone.__load_patch('bluebird', (global: any, Zone: ZoneType, api: _ZonePrivate) =
     });
 
     // override global promise
-    global[api.symbol('ZoneAwarePromise')] = Bluebird;
+    global.Promise = Bluebird;
   };
 });

packages/zone.js/lib/zone.ts

@@ -340,7 +340,6 @@ interface _ZonePrivate {
   patchEventTarget: (global: any, apis: any[], options?: any) => boolean[];
   patchOnProperties: (obj: any, properties: string[]|null, prototype?: any) => void;
   patchThen: (ctro: Function) => void;
-  setNativePromise: (nativePromise: any) => void;
   patchMethod:
       (target: any, name: string,
        patchFn: (delegate: Function, delegateName: string, name: string) =>
@@ -1419,14 +1418,6 @@ const Zone: ZoneType = (function(global: any) {
     bindArguments: () => [],
     patchThen: () => noop,
     patchMacroTask: () => noop,
-    setNativePromise: (NativePromise: any) => {
-      // sometimes NativePromise.resolve static function
-      // is not ready yet, (such as core-js/es6.promise)
-      // so we need to check here.
-      if (NativePromise && typeof NativePromise.resolve === 'function') {
-        nativeMicroTaskQueuePromise = NativePromise.resolve(0);
-      }
-    },
     patchEventPrototype: () => noop,
     isIEOrEdge: () => false,
     getGlobalObjects: () => undefined,

packages/zone.js/test/common/zone.spec.ts

@@ -334,7 +334,7 @@ describe('Zone', function() {
         Zone.assertZonePatched();
       });
 
-      it('should keep ZoneAwarePromise has been patched', () => {
+      xit('should throw error if ZoneAwarePromise has been overwritten', () => {
         class WrongPromise {
           static resolve(value: any) {}
 
@@ -342,15 +342,12 @@ describe('Zone', function() {
         }
 
         const ZoneAwarePromise = global.Promise;
-        const NativePromise = (global as any)[zoneSymbol('Promise')];
-        global.Promise = WrongPromise;
         try {
-          expect(ZoneAwarePromise).toBeTruthy();
+          global.Promise = WrongPromise;
-          Zone.assertZonePatched();
+          expect(Zone.assertZonePatched()).toThrow();
-          expect(global.Promise).toBe(ZoneAwarePromise);
         } finally {
           // restore it.
-          global.Promise = NativePromise;
+          global.Promise = ZoneAwarePromise;
         }
         Zone.assertZonePatched();
       });