Implement Chrome Extension TabCapture API.

chrome/test/data/extensions/api_test/tab_capture/experimental/test.js

+// Copyright (c) 2012 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.
+
+var tabCapture = chrome.experimental.tabCapture;
+
+chrome.test.runTests([
+
+  function getTabMediaInvalidTab() {
+    var tabMediaRequestCallback = function(stream) {
+      chrome.test.assertTrue(stream == undefined);
+      if (!chrome.extension.lastError) {
+        chrome.test.fail();
+      }
+      chrome.test.succeed();
+    };
+
+    tabCapture.getTabMedia(-1, {audio: true, video: true},
+      tabMediaRequestCallback);
+  },
+
+  function getTabMedia() {
+    var tabMediaRequestCallback = function(stream) {
+      // TODO(justinlin): Does not get here yet due to requiring auth input.
+    };
+
+    var gotTabId = function(tab) {
+      console.log('using tab: ' + tab[0].id);
+      tabCapture.getTabMedia(tab[0].id, {audio: true, video: true},
+        chrome.test.callbackPass(tabMediaRequestCallback));
+    };
+
+    chrome.tabs.query({active: true}, gotTabId);
+  },
+
+]);