fix(coreservices): Use Promise.reject()/resolve()/all()

closes #2683

src/justjs.ts

@@ -10,8 +10,8 @@ import {extend, assertPredicate, forEach, applyPairs} from "./common/common";
 
 /** $q-like promise api */
 services.$q = (executor: (resolve, reject) => void) => new Promise(executor);
-services.$q.when = (val) => new Promise((resolve, reject) => resolve(val));
-services.$q.reject = (val) => new Promise((resolve, reject) => { reject(val); });
+services.$q.when = (val) => Promise.resolve(val);
+services.$q.reject = (val) => Promise.reject(val);
 services.$q.defer = function() {
  let deferred: any = {};
  deferred.promise = new Promise((resolve, reject) => {
@@ -24,11 +24,7 @@ services.$q.defer = function() {
 
 services.$q.all = function (promises: { [key: string]: Promise<any> } | Promise<any>[]) {
  if (isArray(promises)) {
- return new Promise((resolve, reject) => {
- let results = [];
- promises.reduce((wait4, promise) => wait4.then(() => promise.then(val => results.push(val))), services.$q.when())
- .then(() => { resolve(results); }, reject);
- });
+ return Promise.all(promises);
  }
 
  if (isObject(promises)) {
@@ -38,6 +34,7 @@ services.$q.all = function (promises: { [key: string]: Promise<any> } | Promise<
  // When each promise resolves, map it to a tuple { key: key, val: val }
  let chain = Object.keys(promises)
  .map(key => promises[key].then(val => ({key, val})));
+
  // Then wait for all promises to resolve, and convert them back to an object
  return services.$q.all(chain).then(values => {
  let value = values.reduce((acc, tuple) => { acc[tuple.key] = tuple.val; return acc; }, {});