Adding Discarded property support for onUpdate function.

chrome/test/data/extensions/api_test/tabs/basics/discarded.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.
+
+var testTab;
+chrome.test.runTests([
+
+    function setupWindow() {
+      var testTabId;
+
+      createWindow(["about:blank", "chrome://newtab/"], {},
+                   pass(function(winId, tabIds) {
+        testTabId = tabIds[1];
+      }));
+
+      waitForAllTabs(pass(function() {
+        queryForTab(testTabId, {}, pass(function(tab) {
+          testTab = tab;
+        }));
+      }));
+    },
+
+    function discard() {
+      // Initially tab isn't discarded.
+      assertFalse(testTab.discarded);
+
+      var onUpdatedCompleted = chrome.test.listenForever(
+          chrome.tabs.onUpdated,
+          function(tabId, changeInfo, tab) {
+        if ('discarded' in changeInfo) {
+          // Make sure it's the right tab.
+          assertEq(testTab.index, tab.index);
+          assertEq(testTab.windowId, tab.windowId);
+
+          // Make sure the discarded state changed correctly.
+          assertTrue(changeInfo.discarded);
+          assertTrue(tab.discarded);
+
+          onUpdatedCompleted();
+        }
+      });
+
+      // TODO(georgesak): Remove tab update when http://crbug.com/632839 is
+      // resolved.
+      // Discard and update testTab (the id changes after a tab is discarded).
+      chrome.tabs.discard(testTab.id, pass(function(tab) {
+        assertTrue(tab.discarded);
+        testTab = tab;
+      }));
+    },
+
+  function reload() {
+    // Tab is already discarded.
+    assertTrue(testTab.discarded);
+
+    var onUpdatedCompleted = chrome.test.listenForever(
+        chrome.tabs.onUpdated,
+        function(tabId, changeInfo, tab) {
+      if ('discarded' in changeInfo) {
+        // Make sure it's the right tab.
+        assertEq(testTab.index, tab.index);
+        assertEq(testTab.windowId, tab.windowId);
+
+        // Make sure the discarded state changed correctly.
+        assertFalse(changeInfo.discarded);
+        assertFalse(tab.discarded);
+
+        onUpdatedCompleted();
+      }
+    });
+
+    chrome.tabs.reload(testTab.id);
+  }
+]);