Implement chrome.brailleDisplayPrivate API

chrome/test/data/extensions/api_test/braille_display_private/key_events/test.js

Index: chrome/test/data/extensions/api_test/braille_display_private/key_events/test.js
diff --git a/chrome/test/data/extensions/api_test/braille_display_private/key_events/test.js b/chrome/test/data/extensions/api_test/braille_display_private/key_events/test.js
new file mode 100644
index 0000000000000000000000000000000000000000..ed3827eb8cd02a94dcc97c502e9e0ce770c3605a
--- /dev/null
+++ b/chrome/test/data/extensions/api_test/braille_display_private/key_events/test.js
@@ -0,0 +1,46 @@
+// Copyright (c) 2013 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.
+
+// Test for brailleDisplayPrivate.onKeyEvent.
+// browser_tests.exe --gtest_filter="BrailleDisplayPrivateApiTest.*"
+
+var pass = chrome.test.callbackPass;
+
+function createBuffer(size, element) {
+  var buf = new Uint8Array(size);
+  for (var i = 0; i < size; ++i) {
+    buf[i] = element;
+  }
+  return buf.buffer;
+}
+
+var EXPECTED_EVENTS = [
+  { "command": "line_up" },
+  { "command": "line_down" },
+]
+
+var event_number = 0;
+var callbackCompleted;
+
+function eventListener(event) {
+  console.log("Received event: " + event);
+  chrome.test.assertEq(event, EXPECTED_EVENTS[event_number]);
+  if (++event_number == EXPECTED_EVENTS.length) {
+    console.log("Happy!");
+    callbackCompleted();
+  }
+  console.log("Event number: " + event_number);
+}
+
+chrome.test.runTests([
+  function testKeyEvents() {
+    chrome.brailleDisplayPrivate.onKeyEvent.addListener(eventListener);
+    callbackCompleted = chrome.test.callbackAdded();
+    chrome.brailleDisplayPrivate.getDisplayState(pass(
+        function(state) {
+          chrome.test.assertTrue(state.available, "Display not available");
+          chrome.test.assertEq(11, state.textCellCount);
+        }));
+  }
+]);