docs(select.SelectController): fix example

Closes #16271
Closes #16275

Author: Narretz

src/ng/directive/select.js

@@ -41,7 +41,8 @@ function setOptionSelectedStatus(optionEl, value) {
  *       <option value="option-1">Option 1</option>
  *       <option value="option-2">Option 2</option>
  *     </select><br>
- *     <span ng-if="myForm.testSelect.$error.unknownValue">Error: The current model doesn't match any option</span>
+ *     <span class="error" ng-if="myForm.testSelect.$error.unknownValue">
+ *       Error: The current model doesn't match any option</span><br>
  *
  *     <button ng-click="forceUnknownOption()">Force unknown option</button><br>
  *   </form>
@@ -90,11 +91,11 @@ function setOptionSelectedStatus(optionEl, value) {
  * <div ng-controller="ExampleController">
  *   <form name="myForm">
  *     <label for="testSelect"> Select: </label><br>
- *     <select name="testSelect" ng-model="selected" unknown-value-required>
+ *     <select name="testSelect" ng-model="selected" required unknown-value-required>
  *       <option value="option-1">Option 1</option>
  *       <option value="option-2">Option 2</option>
  *     </select><br>
- *     <span ng-if="myForm.testSelect.$error.required">Error: Please select a value</span><br>
+ *     <span class="error" ng-if="myForm.testSelect.$error.required">Error: Please select a value</span><br>
  *
  *     <button ng-click="forceUnknownOption()">Force unknown option</button><br>
  *   </form>
@@ -130,6 +131,22 @@ function setOptionSelectedStatus(optionEl, value) {
  *     };
  *   });
  * </file>
+ * <file name="protractor.js" type="protractor">
+ *  it('should show the error message when the unknown option is selected', function() {
+
+      var error = element(by.className('error'));
+
+      expect(error.getText()).toBe('Error: Please select a value');
+
+      element(by.cssContainingText('option', 'Option 1')).click();
+
+      expect(error.isPresent()).toBe(false);
+
+      element(by.tagName('button')).click();
+
+      expect(error.getText()).toBe('Error: Please select a value');
+    });
+ * </file>
  *</example>
  *
  *