Fix autoupdate_EndToEndTest on veyron_rialto

chrome/browser/chromeos/login/screens/network_screen_browsertest.cc

 // 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.
 
 #include "chrome/browser/chromeos/login/screens/network_screen.h"
 
 #include <memory>
 
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/strings/utf_string_conversions.h"
+#include "base/test/test_mock_time_task_runner.h"
 #include "chrome/browser/chromeos/login/enrollment/enrollment_screen.h"
 #include "chrome/browser/chromeos/login/helper.h"
 #include "chrome/browser/chromeos/login/screens/base_screen.h"
 #include "chrome/browser/chromeos/login/screens/mock_base_screen_delegate.h"
 #include "chrome/browser/chromeos/login/test/oobe_screen_waiter.h"
 #include "chrome/browser/chromeos/login/test/wizard_in_process_browser_test.h"
 #include "chrome/browser/chromeos/login/ui/login_display_host.h"
 #include "chrome/browser/chromeos/login/wizard_controller.h"
 #include "chromeos/chromeos_switches.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
@@ skipping 141 matching lines @@
 
  protected:
   void SetUpOnMainThread() override {
     NetworkScreenTest::SetUpOnMainThread();
 
     // Set up fake networks.
     DBusThreadManager::Get()
         ->GetShillManagerClient()
         ->GetTestInterface()
         ->SetupDefaultEnvironment();
+
+    // Set up mock TaskRunner.
+    base::TestMockTimeTaskRunner::ScopedContext scoped_context(

[xiyuan, 2017/04/18 22:45:26]

We need to make ScopedContext a member var of the test so that it will have the
same life time of the test. The original task runner is restored when
ScopedContext is destructed (i.e. go out of scope). That is probably why
FastFoward does not work.

+        task_runner_.get());
   }
 
+  // Replace main thread's task runner with a mock for duration of test.
+  scoped_refptr<base::TestMockTimeTaskRunner> task_runner_ =
+      new base::TestMockTimeTaskRunner();
+
  private:
   // Overridden from InProcessBrowserTest:
   void SetUpCommandLine(base::CommandLine* command_line) override {
     command_line->AppendSwitchASCII(
         switches::kEnterpriseEnableZeroTouchEnrollment, "hands-off");
   }
 
   DISALLOW_COPY_AND_ASSIGN(HandsOffNetworkScreenTest);
 };
 
@@ skipping 67 matching lines @@
   EXPECT_CALL(*mock_network_state_helper_, GetCurrentNetworkName())
       .Times(AnyNumber())
       .WillRepeatedly(Return(base::ASCIIToUTF16("net0")));
   EXPECT_CALL(*mock_network_state_helper_, IsConnected())
       .Times(AnyNumber())
       .WillRepeatedly(Return(true));
 
   // Stop waiting for net0.
   network_screen_->StopWaitingForConnection(base::ASCIIToUTF16("net0"));
 
+  // Fast forward time by 3 minutes.
+  task_runner_->FastForwardBy(base::TimeDelta::FromMinutes(3));
+
   // Check that OnContinueButtonPressed has been called exactly once.
   ASSERT_EQ(1, network_screen_->continue_attempts_);
 
   // Stop waiting for another network, net1.
   network_screen_->StopWaitingForConnection(base::ASCIIToUTF16("net1"));
 
   // Check that OnContinueButtonPressed stil has been called exactly once
   ASSERT_EQ(1, network_screen_->continue_attempts_);
 
   // Wait for the enrollment screen.
   OobeScreenWaiter(OobeScreen::SCREEN_OOBE_ENROLLMENT)
       .WaitNoAssertCurrentScreen();
 
   // Reset the enrollment helper so there is no side effect with other tests.
   static_cast<EnrollmentScreen*>(wizard_controller->current_screen())
       ->enrollment_helper_.reset();
 }
 
 }  // namespace chromeos