Implement input.ime.sendKeyEvents API.

chrome/test/data/extensions/api_test/input_ime_nonchromeos/background.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.
 
 chrome.test.runTests([
   function testActivate() {
     var focused = false;
     var activated = false;
     chrome.input.ime.onFocus.addListener(function(context) {
       if (context.type == 'none') {
@@ skipping 34 matching lines @@
       chrome.test.assertNoLastError()
       chrome.test.assertTrue(!!win);
       chrome.test.assertTrue(win instanceof Window);
       chrome.test.assertFalse(win.document.webkitHidden);
       // test for security origin.
       // If security origin is not correctly set, there will be securtiy
       // exceptions when accessing DOM or add event listeners.
       win.addEventListener('unload', function() {});
       chrome.test.succeed();
     });
+  },
+
+  function testSendKeyEvent() {
+    var key_vent_count = 0;

[Devlin, 2016/03/10 23:21:14]

nit: event, not vent
nit: use js-style here (so keyEventCount).

[Azure Wei, 2016/03/11 07:29:01]

Done.

+
+    chrome.input.ime.onKeyEvent.addListener(function(engineID, keyData) {

[Devlin, 2016/03/10 23:21:14]

Hmm... it's expected behavior to receive key events for the events the extension
itself sends?  What's the use case here?

[Azure Wei, 2016/03/11 07:29:01]

Actually the extension won't handle the key events if they are sent by the
extension itself. This logic was just for keeping consistent with the logic in
ChromeOS. It's fine to not pass the event to the extension, if you feel strongly
wearied about this. Please review the updated codes.    

+      if (key_vent_count == 0) {
+        chrome.test.assertEq(keyData.type, 'keydown');
+      }
+      else if (key_vent_count == 1) {
+        chrome.test.assertEq(keyData.type, 'keyup');
+        chrome.test.succeed();
+      }
+      chrome.test.assertEq(keyData.key, 'a');
+      chrome.test.assertEq(keyData.code, 'KeyA');
+      chrome.test.assertFalse(keyData.ctrlKey);
+      chrome.test.assertFalse(keyData.altKey);
+      chrome.test.assertFalse(keyData.shiftKey);
+      chrome.test.assertFalse(keyData.capsLock);
+      ++key_vent_count;
+      return false;
+    });
+
+    chrome.input.ime.sendKeyEvents({
+      'contextID': 1,
+      'keyData': [{
+        'type': 'keydown',
+        'requestId': '0',
+        'key': 'a',
+        'code': 'KeyA'
+      }, {
+        'type': 'keyup',
+        'requestId': '1',
+        'key': 'a',
+        'code': 'KeyA'
+     }]
+    });
   }
 ]);