Allow webkitSpeechRecognition work from an app's background page.

chrome/test/data/extensions/platform_apps/speech/background_page/test.js

+// Copyright 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.
+
+chrome.app.runtime.onLaunched.addListener(function() {
+  chrome.test.runTests([
+    function testWebkitSpeechRecognition() {
+      var succeeded = false;
+
+      var r = new webkitSpeechRecognition();
+      r.onerror = function(e) {
+        if (succeeded) {
+          return;
+        }
+        chrome.test.fail();
+      };
+      r.onstart = function() {
+        succeeded = true;
+        chrome.test.succeed();
+      };
+      // With FakeSpeechRecognitionManager, we do not get onstart event. We
+      // directly get results instead.
+      r.onresult = function(e) {
+        succeeded = true;
+        chrome.test.assertTrue(e.results.length > 0);
+        var transcript = e.results[0][0].transcript;
+        chrome.test.assertEq('Pictures of the moon', transcript);
+        chrome.test.succeed();
+      };
+      r.start();
+    }
+  ]);
+});