Fix reentrancy bug in NetInternalsTest.NetInternalsDnsViewIncognitoClears.

InProcessBrowserTest::CreateIncognitoBrowser() runs its own message loop
as it waits for navigation to complete, which resulted in a race between
the navigation to about:blank completing and trying to close the
Incognito browser.

BUG=106707

Review URL: http://codereview.chromium.org/8892006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@113898 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/ui/webui/net_internals_ui_browsertest.cc

@@ -121,7 +121,8 @@ class NetInternalsTest : public WebUIBrowserTest {
     // there, and that the background tab exists at slot 1.
     void NavigateToPrerender(const ListValue* list_value);
 
-    // Creates an incognito browser.
+    // Creates an incognito browser.  Once creation is complete, passes a
+    // message to the Javascript test harness.
     void CreateIncognitoBrowser(const ListValue* list_value);
 
     // Closes an incognito browser created with CreateIncognitoBrowser.
@@ -264,6 +265,10 @@ void NetInternalsTest::MessageHandler::CreateIncognitoBrowser(
     const ListValue* list_value) {
   ASSERT_FALSE(incognito_browser_);
   incognito_browser_ = net_internals_test_->CreateIncognitoBrowser();
+
+  // Tell the test harness that creation is complete.
+  StringValue command_value("onIncognitoBrowserCreatedForTest");
+  web_ui()->CallJavascriptFunction("g_browser.receive", command_value);
 }
 
 void NetInternalsTest::MessageHandler::CloseIncognitoBrowser(
@@ -403,11 +408,6 @@ IN_PROC_BROWSER_TEST_F(NetInternalsTest, NetInternalsDnsViewAddTwoTwice) {
 // Makes sure that openning and then closing an incognito window clears the
 // DNS cache.  To keep things simple, we add a fake cache entry ourselves,
 // rather than having the incognito browser create one.
-#if defined(OS_CHROMEOS)
-// http://crbug.com/106707
-#define NetInternalsDnsViewIncognitoClears \
-    FLAKY_NetInternalsDnsViewIncognitoClears
-#endif
 IN_PROC_BROWSER_TEST_F(NetInternalsTest, NetInternalsDnsViewIncognitoClears) {
   EXPECT_TRUE(RunJavascriptAsyncTest("netInternalsDnsViewIncognitoClears"));
 }

chrome/test/data/webui/net_internals/dns_view.js

@@ -258,7 +258,7 @@ netInternalsTest.test('netInternalsDnsViewAddTwoTwice', function() {
 netInternalsTest.test('netInternalsDnsViewIncognitoClears', function() {
   netInternalsTest.switchToView('dns');
   var taskQueue = new netInternalsTest.TaskQueue(true);
-  taskQueue.addTask(netInternalsTest.getCreateIncognitoBrowserTask());
+  taskQueue.addTask(new netInternalsTest.CreateIncognitoBrowserTask());
   taskQueue.addTask(new AddCacheEntryTask(
                         'somewhere.com', '1.2.3.4', 0, true));
   taskQueue.addTask(netInternalsTest.getCloseIncognitoBrowserTask());

chrome/test/data/webui/net_internals/net_internals_test.js

@@ -424,18 +424,51 @@ var netInternalsTest = (function() {
     }
   };
 
-  // Creates an incognito window.  May not be called if there already is an
-  // incognito in exitence.  Returns immediately.
-  function getCreateIncognitoBrowserTask() {
-    return new CallFunctionTask(
-        function() {
-          chrome.send('createIncognitoBrowser');
-        });
+  /**
+   * A Task that creates an incognito window and only completes once it has
+   * navigated to about:blank.  The waiting is required to avoid reentrancy
+   * issues, since the function to create the incognito browser also waits
+   * for the navigation to complete.  May not be called if there's already an
+   * incognito browser in existence.
+   * @constructor
+   */
+  function CreateIncognitoBrowserTask() {
+    Task.call(this);
+  }
+
+  CreateIncognitoBrowserTask.prototype = {
+    __proto__: Task.prototype,
+
+    /**
+     * Tells the browser process to create an incognito browser, and sets
+     * up a callback to be called on completion.
+     */
+    start: function() {
+      // Reuse the BrowserBridge's callback mechanism, since it's already
+      // wrapped in our test harness.
+      assertEquals('undefined',
+                   typeof g_browser.onIncognitoBrowserCreatedForTest);
+      g_browser.onIncognitoBrowserCreatedForTest =
+          this.onIncognitoBrowserCreatedForTest.bind(this);
+
+      chrome.send('createIncognitoBrowser');
+    },
+
+    /**
+     * Deletes the callback function, and completes the task.
+     */
+    onIncognitoBrowserCreatedForTest: function() {
+      delete g_browser.onIncognitoBrowserCreatedForTest;
+      this.onTaskDone();
+    }
   };
 
-  // Closes an incognito window created with the task above.  May only be
-  // called if there's an incognito window created by the above function
-  // that has yet to be closed.  Returns immediately.
+  /**
+   * Returns a task that closes an incognito window created with the task
+   * above.  May only be called if there's an incognito window created by
+   * the above function that has yet to be closed.  Returns immediately.
+   * @return {Task} Task that closes incognito browser window.
+   */
   function getCloseIncognitoBrowserTask() {
     return new CallFunctionTask(
         function() {
@@ -530,7 +563,7 @@ var netInternalsTest = (function() {
     TaskQueue: TaskQueue,
     Task: Task,
     CallFunctionTask: CallFunctionTask,
-    getCreateIncognitoBrowserTask: getCreateIncognitoBrowserTask,
+    CreateIncognitoBrowserTask: CreateIncognitoBrowserTask,
     getCloseIncognitoBrowserTask: getCloseIncognitoBrowserTask,
     Source: Source,
     Event: Event,