WebUI: For cr-dialog, handle Enter keys in paper-inputs.

chrome/test/data/webui/cr_elements/cr_dialog_test.js

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 suite('cr-dialog', function() {
   setup(function() {
     PolymerTest.clearBody();
   });
 
   test('focuses title on show', function() {
@@ skipping 72 matching lines @@
     })
     var clicked = false;
     actionButton.addEventListener('click', function() {
       clicked = true;
     });
 
     MockInteractions.keyEventOn(dialog, 'keypress', 13, undefined, 'Enter');
     assertTrue(clicked);
   });
 
+  test('enter keys from paper-inputs (only) are processed', function() {
+    document.body.innerHTML = `
+      <dialog is="cr-dialog">
+        <div class="title">title</div>
+        <div class="body">
+          <paper-input></paper-input>
+          <foobar></foobar>
+          <button class="action-button">active</button>
+        </div>
+      </dialog>`;
+
+    var dialog = document.body.querySelector('dialog');
+
+    var inputElement = document.body.querySelector('paper-input');
+    var otherElement = document.body.querySelector('foobar');
+    var actionButton = document.body.querySelector('.action-button');
+    assertTrue(!!inputElement);
+    assertTrue(!!otherElement);
+    assertTrue(!!actionButton);
+
+    // MockInteractions triggers event listeners synchronously.
+    var clickedCounter = 0;
+    actionButton.addEventListener('click', function() {
+      clickedCounter += 1;

[dpapad, 2017/04/05 21:34:45]

Nit (optional): clickedCounter++;

[tommycli, 2017/04/05 21:42:48]

Done.

+    });
+
+    MockInteractions.keyEventOn(
+        otherElement, 'keypress', 13, undefined, 'Enter');

[dpapad, 2017/04/05 21:34:45]

Nit (optional): Can we make a helper

function pressEnter(element) {
  MockInteractions.keyEventOn(element, 'keypress', 13, undefined, 'Enter');
}

and re-use it throughout this file (I see 5 occurrences currently).

[tommycli, 2017/04/05 21:42:48]

Done.

+    assertEquals(0, clickedCounter);
+
+    MockInteractions.keyEventOn(
+        inputElement, 'keypress', 13, undefined, 'Enter');
+    assertEquals(1, clickedCounter);
+  });
+
   test('focuses [autofocus] instead of title when present', function() {
     document.body.innerHTML = `
       <dialog is="cr-dialog">
         <div class="title">title</div>
         <div class="body"><button autofocus>button</button></div>
       </dialog>`;
 
     var dialog = document.body.querySelector('dialog');
     var button = document.body.querySelector('button');
 
@@ skipping 33 matching lines @@
       }
     });
     observer.observe(bodyContainer, {attributes: true});
 
     // Height is normally set via CSS, but mixin doesn't work with innerHTML.
     bodyContainer.style.height = '1px';
     bodyContainer.scrollTop = 100;
     dialog.showModal();  // Attach the dialog for the first time here.
   });
 });