FIX: ensures select-kit can select a row with 0 as value (#8955)

app/assets/javascripts/select-kit/components/multi-select.js.es6

@@ -41,7 +41,7 @@ export default SelectKitComponent.extend({
   },
 
   select(value, item) {
-    if (!value || !value.length) {
+    if (!Ember.isPresent(value)) {
       if (!this.validateSelect(this.selectKit.highlighted)) {
         return;
       }

app/assets/javascripts/select-kit/components/select-kit.js.es6

@@ -421,8 +421,8 @@ export default Component.extend(
         }
 
         if (this.singleSelect) {
-          value = value.firstObject || null;
+          value = Ember.isPresent(value.firstObject) ? value.firstObject : null;
-          items = items.firstObject || null;
+          items = Ember.isPresent(items.firstObject) ? items.firstObject : null;
         }
 
         this._boundaryActionHandler("onChange", value, items);
@@ -703,7 +703,7 @@ export default Component.extend(
     },
 
     select(value, item) {
-      if (!value) {
+      if (!Ember.isPresent(value)) {
         if (!this.validateSelect(this.selectKit.highlighted)) {
           return;
         }

test/javascripts/components/select-kit/single-select-test.js.es6

@@ -215,3 +215,26 @@ componentTest("content is a basic array", {
     assert.equal(this.value, null);
   }
 });
+
+componentTest("selected value can be 0", {
+  template: template(),
+
+  beforeEach() {
+    setDefaultState(this, {
+      value: 1,
+      content: [
+        { id: 0, name: "foo" },
+        { id: 1, name: "bar" }
+      ]
+    });
+  },
+
+  async test(assert) {
+    assert.equal(this.subject.header().value(), 1);
+
+    await this.subject.expand();
+    await this.subject.selectRowByValue(0);
+
+    assert.equal(this.subject.header().value(), 0);
+  }
+});

test/javascripts/helpers/select-kit-helper.js.es6

@@ -169,7 +169,7 @@ export default function selectKit(selector) {
     },
 
     async selectRowByName(name) {
-      await selectKitSelectRowByValue(name, selector);
+      await selectKitSelectRowByName(name, selector);
     },
 
     async selectNoneRow() {