DEV: Clean up Ember imports (#8979)

Includes:
* Import `computed` helpers
* Import `@ember/application`
* Import `isBlank` from `@ember/utils`
* Import `A` from `@ember/array`
* Import `EmberArray` from `@ember/array`
* Import `ArrayProxy` from `@ember/array/proxy`
* Import `warn` from `@ember/debug`
* Import `EmberObject` from `@ember/object`
* Import `Application` from `@ember/application`
* Import `EmberRouter` from `@ember/routing/router`
* Import `isPresent` from `@ember/utils`
* Import `computed` from `@ember/object`
* Import `guidFor` from `@ember/object`
* Import `isArray` from `@ember/array`
* Import `TextField` from `@ember/component`
* Import `TextArea` from `@ember/component`
* Import `Promise` from `rsvp`
* Import `Evented` from `@ember/object/evented`
* Replace deprecated `ember-addons/ember-computed-decorators` imports

plugins/discourse-local-dates/assets/javascripts/discourse/components/discourse-local-dates-create-form.js.es6

@@ -1,13 +1,15 @@
+import EmberObject from "@ember/object";
 import { isEmpty } from "@ember/utils";
 import { schedule } from "@ember/runloop";
 import Component from "@ember/component";
+import { notEmpty } from "@ember/object/computed";
+import { Promise } from "rsvp";
 /* global Pikaday:true */
 import { propertyNotEqual } from "discourse/lib/computed";
 import loadScript from "discourse/lib/load-script";
-import computed from "discourse-common/utils/decorators";
+import computed, { observes } from "discourse-common/utils/decorators";
 import { cookAsync } from "discourse/lib/text";
 import discourseDebounce from "discourse/lib/debounce";
-import { observes } from "discourse-common/utils/decorators";
 
 export default Component.extend({
   timeFormat: "HH:mm:ss",
@@ -24,9 +26,9 @@ export default Component.extend({
   isValid: true,
   timezone: null,
   fromSelected: null,
-  fromFilled: Ember.computed.notEmpty("date"),
+  fromFilled: notEmpty("date"),
   toSelected: null,
-  toFilled: Ember.computed.notEmpty("toDate"),
+  toFilled: notEmpty("toDate"),
 
   init() {
     this._super(...arguments);
@@ -113,7 +115,7 @@ export default Component.extend({
       format = "LL";
     }
 
-    return Ember.Object.create({
+    return EmberObject.create({
       date: dateTime.format(this.dateFormat),
       time,
       dateTime,
@@ -146,7 +148,7 @@ export default Component.extend({
       format = "LL";
     }
 
-    return Ember.Object.create({
+    return EmberObject.create({
       date: dateTime.format(this.dateFormat),
       time,
       dateTime,
@@ -157,7 +159,7 @@ export default Component.extend({
 
   @computed("recurring", "timezones", "timezone", "format")
   options(recurring, timezones, timezone, format) {
-    return Ember.Object.create({
+    return EmberObject.create({
       recurring,
       timezones,
       timezone,
@@ -171,7 +173,7 @@ export default Component.extend({
     "options.{recurring,timezones,timezone,format}"
   )
   computedConfig(fromConfig, toConfig, options) {
-    return Ember.Object.create({
+    return EmberObject.create({
       from: fromConfig,
       to: toConfig,
       options
@@ -372,7 +374,7 @@ export default Component.extend({
   },
 
   _setupPicker() {
-    return new Ember.RSVP.Promise(resolve => {
+    return new Promise(resolve => {
       loadScript("/javascripts/pikaday.js").then(() => {
         const options = {
           field: this.$(`.fake-input`)[0],

plugins/discourse-presence/assets/javascripts/discourse/components/composer-presence-display.js.es6

@@ -2,6 +2,8 @@ import { once } from "@ember/runloop";
 import { debounce } from "@ember/runloop";
 import { cancel } from "@ember/runloop";
 import Component from "@ember/component";
+import { equal, gt } from "@ember/object/computed";
+import { Promise } from "rsvp";
 import { ajax } from "discourse/lib/ajax";
 import computed, { observes, on } from "discourse-common/utils/decorators";
 
@@ -22,6 +24,9 @@ export default Component.extend({
   presenceUsers: null,
   channel: null,
 
+  isReply: equal("action", "reply"),
+  shouldDisplay: gt("users.length", 0),
+
   @on("didInsertElement")
   composerOpened() {
     this._lastPublish = new Date();
@@ -113,7 +118,7 @@ export default Component.extend({
 
     // Don't publish presence if disabled
     if (this.currentUser.hide_profile_and_presence) {
-      return Ember.RSVP.Promise.resolve();
+      return Promise.resolve();
     }
 
     return ajax("/presence/publish", { type: "POST", data });
@@ -122,8 +127,5 @@ export default Component.extend({
   @computed("presenceUsers", "currentUser.id")
   users(users, currentUserId) {
     return (users || []).filter(user => user.id !== currentUserId);
-  },
-
-  isReply: Ember.computed.equal("action", "reply"),
-  shouldDisplay: Ember.computed.gt("users.length", 0)
+  }
 });

plugins/discourse-presence/assets/javascripts/discourse/components/topic-presence-display.js.es6

@@ -1,6 +1,7 @@
 import { debounce } from "@ember/runloop";
 import { cancel } from "@ember/runloop";
 import Component from "@ember/component";
+import { gt } from "@ember/object/computed";
 import computed, { on } from "discourse-common/utils/decorators";
 import {
   keepAliveDuration,
@@ -13,6 +14,8 @@ export default Component.extend({
   topicId: null,
   presenceUsers: null,
 
+  shouldDisplay: gt("users.length", 0),
+
   clear() {
     if (!this.isDestroyed) this.set("presenceUsers", []);
   },
@@ -53,7 +56,5 @@ export default Component.extend({
       user =>
         user.id !== currentUser.id && !ignoredUsers.includes(user.username)
     );
-  },
-
-  shouldDisplay: Ember.computed.gt("users.length", 0)
+  }
 });

plugins/poll/assets/javascripts/initializers/extend-for-poll.js.es6

@@ -1,3 +1,4 @@
+import EmberObject from "@ember/object";
 import { withPluginApi } from "discourse/lib/plugin-api";
 import { observes } from "discourse-common/utils/decorators";
 import { getRegister } from "discourse-common/lib/get-owner";
@@ -44,7 +45,7 @@ function initializePolls(api) {
           if (existing) {
             this._polls[p.name].setProperties(p);
           } else {
-            this._polls[p.name] = Ember.Object.create(p);
+            this._polls[p.name] = EmberObject.create(p);
           }
         });
         this.set("pollsObject", this._polls);
@@ -78,8 +79,8 @@ function initializePolls(api) {
       if (quotedId) {
         const quotedPost = post.quoted[quotedId];
         if (quotedPost) {
-          post = Ember.Object.create(quotedPost);
-          poll = Ember.Object.create(
+          post = EmberObject.create(quotedPost);
+          poll = EmberObject.create(
             quotedPost.polls.find(p => p.name === pollName)
           );
           vote = quotedPost.polls_votes || {};

plugins/poll/test/javascripts/widgets/discourse-poll-standard-results-test.js.es6

@@ -1,4 +1,6 @@
+import EmberObject from "@ember/object";
 import { moduleForWidget, widgetTest } from "helpers/widget-test";
+
 moduleForWidget("discourse-poll-standard-results");
 
 const template = `{{mount-widget
@@ -11,7 +13,7 @@ widgetTest("options in descending order", {
   beforeEach() {
     this.set(
       "poll",
-      Ember.Object.create({
+      EmberObject.create({
         options: [{ votes: 5 }, { votes: 4 }],
         voters: 9
       })
@@ -30,7 +32,7 @@ widgetTest("options in ascending order", {
   beforeEach() {
     this.set(
       "poll",
-      Ember.Object.create({
+      EmberObject.create({
         options: [{ votes: 4 }, { votes: 5 }],
         voters: 9
       })
@@ -50,7 +52,7 @@ widgetTest("multiple options in descending order", {
     this.set("isMultiple", true);
     this.set(
       "poll",
-      Ember.Object.create({
+      EmberObject.create({
         type: "multiple",
         options: [
           { votes: 5, html: "a" },