chrome/test/base/in_process_browser_test.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/test/base/in_process_browser_test.h"
   6
   7 #include "base/auto_reset.h"
   8 #include "base/basictypes.h"
   9 #include "base/bind.h"
  10 #include "base/command_line.h"
  11 #include "base/files/file_path.h"
  12 #include "base/files/file_util.h"
  13 #include "base/lazy_instance.h"
  14 #include "base/location.h"
  15 #include "base/path_service.h"
  16 #include "base/single_thread_task_runner.h"
  17 #include "base/strings/string_number_conversions.h"
  18 #include "base/test/test_file_util.h"
  19 #include "base/thread_task_runner_handle.h"
  20 #include "base/threading/non_thread_safe.h"
  21 #include "chrome/browser/browser_process.h"
  22 #include "chrome/browser/lifetime/application_lifetime.h"
  23 #include "chrome/browser/net/net_error_tab_helper.h"
  24 #include "chrome/browser/profiles/profile.h"
  25 #include "chrome/browser/profiles/profile_manager.h"
  26 #include "chrome/browser/ui/browser.h"
  27 #include "chrome/browser/ui/browser_finder.h"
  28 #include "chrome/browser/ui/browser_list.h"
  29 #include "chrome/browser/ui/browser_list_observer.h"
  30 #include "chrome/browser/ui/browser_navigator.h"
  31 #include "chrome/browser/ui/browser_tabstrip.h"
  32 #include "chrome/browser/ui/browser_window.h"
  33 #include "chrome/browser/ui/host_desktop.h"
  34 #include "chrome/browser/ui/tabs/tab_strip_model.h"
  35 #include "chrome/common/chrome_constants.h"
  36 #include "chrome/common/chrome_paths.h"
  37 #include "chrome/common/chrome_switches.h"
  38 #include "chrome/common/logging_chrome.h"
  39 #include "chrome/common/url_constants.h"
  40 #include "chrome/renderer/chrome_content_renderer_client.h"
  41 #include "chrome/test/base/chrome_test_suite.h"
  42 #include "chrome/test/base/test_launcher_utils.h"
  43 #include "chrome/test/base/test_switches.h"
  44 #include "chrome/test/base/testing_browser_process.h"
  45 #include "components/google/core/browser/google_util.h"
  46 #include "components/os_crypt/os_crypt.h"
  47 #include "content/public/browser/notification_service.h"
  48 #include "content/public/browser/notification_types.h"
  49 #include "content/public/test/browser_test_utils.h"
  50 #include "content/public/test/test_launcher.h"
  51 #include "content/public/test/test_navigation_observer.h"
  52 #include "net/test/embedded_test_server/embedded_test_server.h"
  53 #include "net/test/spawned_test_server/spawned_test_server.h"
  54
  55 #if defined(OS_MACOSX)
  56 #include "base/mac/scoped_nsautorelease_pool.h"
  57 #endif
  58
  59 #if defined(OS_WIN)
  60 #include "base/win/scoped_com_initializer.h"
  61 #include "base/win/windows_version.h"
  62 #include "ui/base/win/atl_module.h"
  63 #include "win8/test/metro_registration_helper.h"
  64 #include "win8/test/test_registrar_constants.h"
  65 #endif
  66
  67 #if defined(ENABLE_CAPTIVE_PORTAL_DETECTION)
  68 #include "chrome/browser/captive_portal/captive_portal_service.h"
  69 #endif
  70
  71 #if !defined(OS_ANDROID) && !defined(OS_IOS)
  72 #include "components/storage_monitor/test_storage_monitor.h"
  73 #endif
  74
  75 #if defined(OS_CHROMEOS)
  76 #include "chrome/browser/chromeos/input_method/input_method_configuration.h"
  77 #endif
  78
  79 namespace {
  80
  81 // Passed as value of kTestType.
  82 const char kBrowserTestType[] = "browser";
  83
  84 // A BrowserListObserver that makes sure that all browsers created are on the
  85 // |allowed_desktop_|.
  86 class SingleDesktopTestObserver : public chrome::BrowserListObserver,
  87                                   public base::NonThreadSafe {
  88  public:
  89   explicit SingleDesktopTestObserver(chrome::HostDesktopType allowed_desktop);
  90   ~SingleDesktopTestObserver() override;
  91
  92   // chrome::BrowserListObserver:
  93   void OnBrowserAdded(Browser* browser) override;
  94
  95  private:
  96   chrome::HostDesktopType allowed_desktop_;
  97
  98   DISALLOW_COPY_AND_ASSIGN(SingleDesktopTestObserver);
  99 };
 100
 101 SingleDesktopTestObserver::SingleDesktopTestObserver(
 102     chrome::HostDesktopType allowed_desktop)
 103         : allowed_desktop_(allowed_desktop) {
 104   BrowserList::AddObserver(this);
 105 }
 106
 107 SingleDesktopTestObserver::~SingleDesktopTestObserver() {
 108   BrowserList::RemoveObserver(this);
 109 }
 110
 111 void SingleDesktopTestObserver::OnBrowserAdded(Browser* browser) {
 112   CHECK(CalledOnValidThread());
 113   CHECK_EQ(browser->host_desktop_type(), allowed_desktop_);
 114 }
 115
 116 }  // namespace
 117
 118 // Library used for testing accessibility.
 119 const base::FilePath::CharType kAXSTesting[] =
 120     FILE_PATH_LITERAL("third_party/accessibility-audit/axs_testing.js");
 121 // JavaScript snippet to configure and run the accessibility audit.
 122 const char kAccessibilityTestString[] =
 123     "var config = new axs.AuditConfiguration();"
 124     "/* Disable warning about rules that cannot be checked. */"
 125     "config.showUnsupportedRulesWarning = false;"
 126     "config.auditRulesToIgnore = ["
 127     "  /*"
 128     "   * The 'elements with meaningful background image' accessibility"
 129     "   * audit (AX_IMAGE_01) does not apply, since Chrome doesn't"
 130     "   * disable background images in high-contrast mode like some"
 131     "   * browsers do."
 132     "   */"
 133     "  'elementsWithMeaningfulBackgroundImage',"
 134     "  /*"
 135     "   * Most WebUI pages are inside an IFrame, so the 'web page should"
 136     "   * have a title that describes topic or purpose' test (AX_TITLE_01)"
 137     "   * generally does not apply."
 138     "   */"
 139     "  'pageWithoutTitle',"
 140     "  /*"
 141     "   * Enable when crbug.com/267035 is fixed."
 142     "   * Until then it's just noise."
 143     "   */"
 144     "  'lowContrastElements'"
 145     "];"
 146     "var result = axs.Audit.run(config);"
 147     "var error = '';"
 148     "for (var i = 0; i < result.length; ++i) {"
 149     "  if (result[i].result == axs.constants.AuditResult.FAIL) {"
 150     "    error = axs.Audit.createReport(result);"
 151     "    break;"
 152     "  }"
 153     "}"
 154     "domAutomationController.send(error);";
 155
 156 InProcessBrowserTest::InProcessBrowserTest()
 157     : browser_(NULL),
 158       exit_when_last_browser_closes_(true),
 159       open_about_blank_on_browser_launch_(true),
 160       multi_desktop_test_(false),
 161       run_accessibility_checks_for_test_case_(false)
 162 #if defined(OS_MACOSX)
 163       , autorelease_pool_(NULL)
 164 #endif  // OS_MACOSX
 165     {
 166 #if defined(OS_MACOSX)
 167   // TODO(phajdan.jr): Make browser_tests self-contained on Mac, remove this.
 168   // Before we run the browser, we have to hack the path to the exe to match
 169   // what it would be if Chrome was running, because it is used to fork renderer
 170   // processes, on Linux at least (failure to do so will cause a browser_test to
 171   // be run instead of a renderer).
 172   base::FilePath chrome_path;
 173   CHECK(PathService::Get(base::FILE_EXE, &chrome_path));
 174   chrome_path = chrome_path.DirName();
 175   chrome_path = chrome_path.Append(chrome::kBrowserProcessExecutablePath);
 176   CHECK(PathService::Override(base::FILE_EXE, chrome_path));
 177 #endif  // defined(OS_MACOSX)
 178
 179   CreateTestServer(base::FilePath(FILE_PATH_LITERAL("chrome/test/data")));
 180   base::FilePath src_dir;
 181   CHECK(PathService::Get(base::DIR_SOURCE_ROOT, &src_dir));
 182   base::FilePath test_data_dir = src_dir.AppendASCII("chrome/test/data");
 183   embedded_test_server()->ServeFilesFromDirectory(test_data_dir);
 184
 185   // chrome::DIR_TEST_DATA isn't going to be setup until after we call
 186   // ContentMain. However that is after tests' constructors or SetUp methods,
 187   // which sometimes need it. So just override it.
 188   CHECK(PathService::Override(chrome::DIR_TEST_DATA, test_data_dir));
 189 }
 190
 191 InProcessBrowserTest::~InProcessBrowserTest() {
 192 }
 193
 194 void InProcessBrowserTest::SetUp() {
 195   // Browser tests will create their own g_browser_process later.
 196   DCHECK(!g_browser_process);
 197
 198   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
 199
 200   // Auto-reload breaks many browser tests, which assume error pages won't be
 201   // reloaded out from under them. Tests that expect or desire this behavior can
 202   // append switches::kEnableOfflineAutoReload, which will override the disable
 203   // here.
 204   command_line->AppendSwitch(switches::kDisableOfflineAutoReload);
 205
 206   // Allow subclasses to change the command line before running any tests.
 207   SetUpCommandLine(command_line);
 208   // Add command line arguments that are used by all InProcessBrowserTests.
 209   PrepareTestCommandLine(command_line);
 210
 211   // Create a temporary user data directory if required.
 212   ASSERT_TRUE(CreateUserDataDirectory())
 213       << "Could not create user data directory.";
 214
 215   // Allow subclasses the opportunity to make changes to the default user data
 216   // dir before running any tests.
 217   ASSERT_TRUE(SetUpUserDataDirectory())
 218       << "Could not set up user data directory.";
 219
 220 #if defined(OS_CHROMEOS)
 221   // Make sure that the log directory exists.
 222   base::FilePath log_dir = logging::GetSessionLogFile(*command_line).DirName();
 223   base::CreateDirectory(log_dir);
 224   // Disable IME extension loading to avoid many browser tests failures.
 225   chromeos::input_method::DisableExtensionLoading();
 226 #endif  // defined(OS_CHROMEOS)
 227
 228 #if defined(OS_MACOSX)
 229   // Always use the MockKeychain if OS encription is used (which is when
 230   // anything sensitive gets stored, including Cookies).  Without this,
 231   // many tests will hang waiting for a user to approve KeyChain access.
 232   OSCrypt::UseMockKeychain(true);
 233 #endif
 234
 235 #if defined(ENABLE_CAPTIVE_PORTAL_DETECTION)
 236   CaptivePortalService::set_state_for_testing(
 237       CaptivePortalService::DISABLED_FOR_TESTING);
 238 #endif
 239
 240   chrome_browser_net::NetErrorTabHelper::set_state_for_testing(
 241       chrome_browser_net::NetErrorTabHelper::TESTING_FORCE_DISABLED);
 242
 243   google_util::SetMockLinkDoctorBaseURLForTesting();
 244
 245 #if defined(OS_WIN)
 246   base::win::Version version = base::win::GetVersion();
 247   // Although Ash officially is only supported for users on Win7+, we still run
 248   // ash_unittests on Vista builders, so we still need to initialize COM.
 249   if (version >= base::win::VERSION_VISTA &&
 250       base::CommandLine::ForCurrentProcess()->HasSwitch(
 251           switches::kAshBrowserTests)) {
 252     com_initializer_.reset(new base::win::ScopedCOMInitializer());
 253     ui::win::CreateATLModuleIfNeeded();
 254     if (version >= base::win::VERSION_WIN8)
 255       ASSERT_TRUE(win8::MakeTestDefaultBrowserSynchronously());
 256   }
 257 #endif
 258
 259   BrowserTestBase::SetUp();
 260 }
 261
 262 void InProcessBrowserTest::PrepareTestCommandLine(
 263     base::CommandLine* command_line) {
 264   // Propagate commandline settings from test_launcher_utils.
 265   test_launcher_utils::PrepareBrowserCommandLineForTests(command_line);
 266
 267   // This is a Browser test.
 268   command_line->AppendSwitchASCII(switches::kTestType, kBrowserTestType);
 269
 270 #if defined(OS_WIN)
 271   if (command_line->HasSwitch(switches::kAshBrowserTests)) {
 272     command_line->AppendSwitchNative(switches::kViewerLaunchViaAppId,
 273                                      win8::test::kDefaultTestAppUserModelId);
 274     // Ash already launches with a single browser opened, add kSilentLaunch to
 275     // make sure StartupBrowserCreator doesn't attempt to launch a browser on
 276     // the native desktop on startup.
 277     command_line->AppendSwitch(switches::kSilentLaunch);
 278   }
 279 #endif
 280
 281 #if defined(OS_MACOSX)
 282   // Explicitly set the path of the binary used for child processes, otherwise
 283   // they'll try to use browser_tests which doesn't contain ChromeMain.
 284   base::FilePath subprocess_path;
 285   PathService::Get(base::FILE_EXE, &subprocess_path);
 286   // Recreate the real environment, run the helper within the app bundle.
 287   subprocess_path = subprocess_path.DirName().DirName();
 288   DCHECK_EQ(subprocess_path.BaseName().value(), "Contents");
 289   subprocess_path =
 290       subprocess_path.Append("Versions").Append(chrome::kChromeVersion);
 291   subprocess_path =
 292       subprocess_path.Append(chrome::kHelperProcessExecutablePath);
 293   command_line->AppendSwitchPath(switches::kBrowserSubprocessPath,
 294                                  subprocess_path);
 295 #endif
 296
 297   // TODO(pkotwicz): Investigate if we can remove this switch.
 298   if (exit_when_last_browser_closes_)
 299     command_line->AppendSwitch(switches::kDisableZeroBrowsersOpenForTests);
 300
 301   if (open_about_blank_on_browser_launch_ && command_line->GetArgs().empty())
 302     command_line->AppendArg(url::kAboutBlankURL);
 303 }
 304
 305 bool InProcessBrowserTest::RunAccessibilityChecks(std::string* error_message) {
 306   if (!browser()) {
 307     *error_message = "browser is NULL";
 308     return false;
 309   }
 310   auto tab_strip = browser()->tab_strip_model();
 311   if (!tab_strip) {
 312     *error_message = "tab_strip is NULL";
 313     return false;
 314   }
 315   auto web_contents = tab_strip->GetActiveWebContents();
 316   if (!web_contents) {
 317     *error_message = "web_contents is NULL";
 318     return false;
 319   }
 320   auto focused_frame = web_contents->GetFocusedFrame();
 321   if (!focused_frame) {
 322     *error_message = "focused_frame is NULL";
 323     return false;
 324   }
 325
 326   // Load accessibility library.
 327   base::FilePath src_dir;
 328   if (!PathService::Get(base::DIR_SOURCE_ROOT, &src_dir)) {
 329     *error_message = "PathService::Get failed";
 330     return false;
 331   }
 332   base::FilePath script_path = src_dir.Append(kAXSTesting);
 333   std::string script;
 334   if (!base::ReadFileToString(script_path, &script)) {
 335     *error_message = "Could not read accessibility library";
 336     return false;
 337   }
 338   if (!content::ExecuteScript(web_contents, script)) {
 339     *error_message = "Failed to load accessibility library";
 340     return false;
 341   }
 342
 343   // Run accessibility audit.
 344   if (!content::ExecuteScriptAndExtractString(focused_frame,
 345                                               kAccessibilityTestString,
 346                                               error_message)) {
 347     *error_message = "Failed to run accessibility audit";
 348     return false;
 349   }
 350
 351   // Test result should be empty if there are no errors.
 352   return error_message->empty();
 353 }
 354
 355 bool InProcessBrowserTest::CreateUserDataDirectory() {
 356   base::CommandLine* command_line = base::CommandLine::ForCurrentProcess();
 357   base::FilePath user_data_dir =
 358       command_line->GetSwitchValuePath(switches::kUserDataDir);
 359   if (user_data_dir.empty()) {
 360     if (temp_user_data_dir_.CreateUniqueTempDir() &&
 361         temp_user_data_dir_.IsValid()) {
 362       user_data_dir = temp_user_data_dir_.path();
 363     } else {
 364       LOG(ERROR) << "Could not create temporary user data directory \""
 365                  << temp_user_data_dir_.path().value() << "\".";
 366       return false;
 367     }
 368   }
 369   return test_launcher_utils::OverrideUserDataDir(user_data_dir);
 370 }
 371
 372 void InProcessBrowserTest::TearDown() {
 373   DCHECK(!g_browser_process);
 374 #if defined(OS_WIN)
 375   com_initializer_.reset();
 376 #endif
 377   BrowserTestBase::TearDown();
 378 }
 379
 380 // TODO(alexmos): This function should expose success of the underlying
 381 // navigation to tests, which should make sure navigations succeed when
 382 // appropriate. See https://crbug.com/425335
 383 void InProcessBrowserTest::AddTabAtIndexToBrowser(
 384     Browser* browser,
 385     int index,
 386     const GURL& url,
 387     ui::PageTransition transition,
 388     bool check_navigation_success) {
 389   chrome::NavigateParams params(browser, url, transition);
 390   params.tabstrip_index = index;
 391   params.disposition = NEW_FOREGROUND_TAB;
 392   chrome::Navigate(&params);
 393
 394   if (check_navigation_success)
 395     content::WaitForLoadStop(params.target_contents);
 396   else
 397     content::WaitForLoadStopWithoutSuccessCheck(params.target_contents);
 398 }
 399
 400 void InProcessBrowserTest::AddTabAtIndex(
 401     int index,
 402     const GURL& url,
 403     ui::PageTransition transition) {
 404   AddTabAtIndexToBrowser(browser(), index, url, transition, true);
 405 }
 406
 407 bool InProcessBrowserTest::SetUpUserDataDirectory() {
 408   return true;
 409 }
 410
 411 // Creates a browser with a single tab (about:blank), waits for the tab to
 412 // finish loading and shows the browser.
 413 Browser* InProcessBrowserTest::CreateBrowser(Profile* profile) {
 414   Browser* browser = new Browser(
 415       Browser::CreateParams(profile, chrome::GetActiveDesktop()));
 416   AddBlankTabAndShow(browser);
 417   return browser;
 418 }
 419
 420 Browser* InProcessBrowserTest::CreateIncognitoBrowser() {
 421   // Create a new browser with using the incognito profile.
 422   Browser* incognito = new Browser(
 423       Browser::CreateParams(browser()->profile()->GetOffTheRecordProfile(),
 424                             chrome::GetActiveDesktop()));
 425   AddBlankTabAndShow(incognito);
 426   return incognito;
 427 }
 428
 429 Browser* InProcessBrowserTest::CreateBrowserForPopup(Profile* profile) {
 430   Browser* browser =
 431       new Browser(Browser::CreateParams(Browser::TYPE_POPUP, profile,
 432                   chrome::GetActiveDesktop()));
 433   AddBlankTabAndShow(browser);
 434   return browser;
 435 }
 436
 437 Browser* InProcessBrowserTest::CreateBrowserForApp(
 438     const std::string& app_name,
 439     Profile* profile) {
 440   Browser* browser = new Browser(
 441       Browser::CreateParams::CreateForApp(
 442           app_name, false /* trusted_source */, gfx::Rect(), profile,
 443           chrome::GetActiveDesktop()));
 444   AddBlankTabAndShow(browser);
 445   return browser;
 446 }
 447
 448 void InProcessBrowserTest::AddBlankTabAndShow(Browser* browser) {
 449   content::WindowedNotificationObserver observer(
 450       content::NOTIFICATION_LOAD_STOP,
 451       content::NotificationService::AllSources());
 452   chrome::AddSelectedTabWithURL(browser,
 453                                 GURL(url::kAboutBlankURL),
 454                                 ui::PAGE_TRANSITION_AUTO_TOPLEVEL);
 455   observer.Wait();
 456
 457   browser->window()->Show();
 458 }
 459
 460 #if !defined(OS_MACOSX)
 461 base::CommandLine InProcessBrowserTest::GetCommandLineForRelaunch() {
 462   base::CommandLine new_command_line(
 463       base::CommandLine::ForCurrentProcess()->GetProgram());
 464   base::CommandLine::SwitchMap switches =
 465       base::CommandLine::ForCurrentProcess()->GetSwitches();
 466   switches.erase(switches::kUserDataDir);
 467   switches.erase(content::kSingleProcessTestsFlag);
 468   switches.erase(switches::kSingleProcess);
 469   new_command_line.AppendSwitch(content::kLaunchAsBrowser);
 470
 471   base::FilePath user_data_dir;
 472   PathService::Get(chrome::DIR_USER_DATA, &user_data_dir);
 473   new_command_line.AppendSwitchPath(switches::kUserDataDir, user_data_dir);
 474
 475   for (base::CommandLine::SwitchMap::const_iterator iter = switches.begin();
 476        iter != switches.end(); ++iter) {
 477     new_command_line.AppendSwitchNative((*iter).first, (*iter).second);
 478   }
 479   return new_command_line;
 480 }
 481 #endif
 482
 483 void InProcessBrowserTest::RunTestOnMainThreadLoop() {
 484   // Pump startup related events.
 485   content::RunAllPendingInMessageLoop();
 486
 487   chrome::HostDesktopType active_desktop = chrome::GetActiveDesktop();
 488   // Self-adds/removes itself from the BrowserList observers.
 489   scoped_ptr<SingleDesktopTestObserver> single_desktop_test_observer;
 490   if (!multi_desktop_test_) {
 491     single_desktop_test_observer.reset(
 492         new SingleDesktopTestObserver(active_desktop));
 493   }
 494
 495   const BrowserList* active_browser_list =
 496       BrowserList::GetInstance(active_desktop);
 497   if (!active_browser_list->empty()) {
 498     browser_ = active_browser_list->get(0);
 499 #if defined(USE_ASH)
 500     // There are cases where windows get created maximized by default.
 501     if (browser_->window()->IsMaximized())
 502       browser_->window()->Restore();
 503 #endif
 504     content::WaitForLoadStop(
 505         browser_->tab_strip_model()->GetActiveWebContents());
 506   }
 507
 508 #if !defined(OS_ANDROID) && !defined(OS_IOS)
 509   // Do not use the real StorageMonitor for tests, which introduces another
 510   // source of variability and potential slowness.
 511   ASSERT_TRUE(storage_monitor::TestStorageMonitor::CreateForBrowserTests());
 512 #endif
 513
 514 #if defined(OS_MACOSX)
 515   // On Mac, without the following autorelease pool, code which is directly
 516   // executed (as opposed to executed inside a message loop) would autorelease
 517   // objects into a higher-level pool. This pool is not recycled in-sync with
 518   // the message loops' pools and causes problems with code relying on
 519   // deallocation via an autorelease pool (such as browser window closure and
 520   // browser shutdown). To avoid this, the following pool is recycled after each
 521   // time code is directly executed.
 522   autorelease_pool_ = new base::mac::ScopedNSAutoreleasePool;
 523 #endif
 524
 525   // Pump any pending events that were created as a result of creating a
 526   // browser.
 527   content::RunAllPendingInMessageLoop();
 528
 529   // run_accessibility_checks_for_test_case_ must be set before calling
 530   // SetUpOnMainThread or RunTestOnMainThread so that one or all tests can
 531   // enable/disable the accessibility audit.
 532   run_accessibility_checks_for_test_case_ = false;
 533
 534   SetUpOnMainThread();
 535 #if defined(OS_MACOSX)
 536   autorelease_pool_->Recycle();
 537 #endif
 538
 539   if (!HasFatalFailure())
 540     RunTestOnMainThread();
 541 #if defined(OS_MACOSX)
 542   autorelease_pool_->Recycle();
 543 #endif
 544
 545   if (run_accessibility_checks_for_test_case_) {
 546     std::string error_message;
 547     EXPECT_TRUE(RunAccessibilityChecks(&error_message));
 548     EXPECT_EQ("", error_message);
 549   }
 550
 551   // Invoke cleanup and quit even if there are failures. This is similar to
 552   // gtest in that it invokes TearDown even if Setup fails.
 553   TearDownOnMainThread();
 554 #if defined(OS_MACOSX)
 555   autorelease_pool_->Recycle();
 556 #endif
 557
 558   // Sometimes tests leave Quit tasks in the MessageLoop (for shame), so let's
 559   // run all pending messages here to avoid preempting the QuitBrowsers tasks.
 560   // TODO(jbates) Once crbug.com/134753 is fixed, this can be removed because it
 561   // will not be possible to post Quit tasks.
 562   content::RunAllPendingInMessageLoop();
 563
 564   QuitBrowsers();
 565   // All BrowserLists should be empty at this point.
 566   for (chrome::HostDesktopType t = chrome::HOST_DESKTOP_TYPE_FIRST;
 567        t < chrome::HOST_DESKTOP_TYPE_COUNT;
 568        t = static_cast<chrome::HostDesktopType>(t + 1)) {
 569     CHECK(BrowserList::GetInstance(t)->empty()) << t;
 570   }
 571 }
 572
 573 void InProcessBrowserTest::QuitBrowsers() {
 574   if (chrome::GetTotalBrowserCount() == 0) {
 575     chrome::NotifyAppTerminating();
 576     return;
 577   }
 578
 579   // Invoke AttemptExit on a running message loop.
 580   // AttemptExit exits the message loop after everything has been
 581   // shut down properly.
 582   base::ThreadTaskRunnerHandle::Get()->PostTask(
 583       FROM_HERE, base::Bind(&chrome::AttemptExit));
 584   content::RunMessageLoop();
 585
 586 #if defined(OS_MACOSX)
 587   // chrome::AttemptExit() will attempt to close all browsers by deleting
 588   // their tab contents. The last tab contents being removed triggers closing of
 589   // the browser window.
 590   //
 591   // On the Mac, this eventually reaches
 592   // -[BrowserWindowController windowWillClose:], which will post a deferred
 593   // -autorelease on itself to ultimately destroy the Browser object. The line
 594   // below is necessary to pump these pending messages to ensure all Browsers
 595   // get deleted.
 596   content::RunAllPendingInMessageLoop();
 597   delete autorelease_pool_;
 598   autorelease_pool_ = NULL;
 599 #endif
 600 }