Fix Volume slider is captured in screenshot done in touchview mode

ash/wm/lock_state_controller_unittest.cc

 // Copyright 2013 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 "ash/wm/lock_state_controller.h"
 
 #include <memory>
 #include <utility>
 
 #include "ash/common/session/session_state_delegate.h"
 #include "ash/common/wm/maximize_mode/maximize_mode_controller.h"
 #include "ash/common/wm_shell.h"
 #include "ash/shell.h"
 #include "ash/test/ash_test_base.h"
 #include "ash/test/test_lock_state_controller_delegate.h"
 #include "ash/test/test_screenshot_delegate.h"
 #include "ash/test/test_session_state_animator.h"
 #include "ash/test/test_shell_delegate.h"
 #include "ash/wm/power_button_controller.h"
 #include "ash/wm/session_state_animator.h"
 #include "base/memory/scoped_vector.h"
+#include "base/run_loop.h"
+#include "base/task_runner.h"
+#include "base/threading/thread_task_runner_handle.h"
 #include "base/time/time.h"
 #include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/fake_session_manager_client.h"
 #include "ui/display/chromeos/display_configurator.h"
 #include "ui/display/chromeos/test/test_display_snapshot.h"
 #include "ui/display/types/display_constants.h"
 #include "ui/events/test/event_generator.h"
 #include "ui/gfx/geometry/size.h"
 
 namespace ash {
 namespace test {
 namespace {
 
+const int kWaitVolumeSliderHiddenInMs = 200;
+
 bool cursor_visible() {
   return Shell::GetInstance()->cursor_manager()->IsCursorVisible();
 }
 
 void CheckCalledCallback(bool* flag) {
   if (flag)
     (*flag) = true;
 }
 
+void WaitUntilVolumeSliderHidden() {
+  base::RunLoop run_loop;
+  base::ThreadTaskRunnerHandle::Get()->PostDelayedTask(
+      FROM_HERE, run_loop.QuitClosure(),
+      base::TimeDelta::FromMilliseconds(kWaitVolumeSliderHiddenInMs));
+  run_loop.Run();
+}
+
 }  // namespace
 
 class LockStateControllerTest : public AshTestBase {
  public:
   LockStateControllerTest()
       : power_button_controller_(nullptr),
         lock_state_controller_(nullptr),
         lock_state_controller_delegate_(nullptr),
         session_manager_client_(nullptr),
         test_animator_(nullptr) {}
@@ skipping 989 matching lines @@
   PressVolumeDown();
   ReleaseVolumeDown();
   EXPECT_EQ(0, delegate->handle_take_screenshot_count());
 
   // Holding volume down and pressing power takes a screenshot.
   ASSERT_EQ(0, delegate->handle_take_screenshot_count());
   PressVolumeDown();
   PressPowerButton();
   ReleasePowerButton();
   ReleaseVolumeDown();
+  WaitUntilVolumeSliderHidden();
   EXPECT_EQ(1, delegate->handle_take_screenshot_count());
 }
 
 // Tests that a lock action is cancellable when quick lock is turned on and
 // maximize mode is not active.
 TEST_F(LockStateControllerTest, QuickLockWhileNotInMaximizeMode) {
   Initialize(false, LoginStatus::USER);
   power_button_controller_->set_enable_quick_lock_for_test(true);
   EnableMaximizeMode(false);
 
@@ skipping 24 matching lines @@
   ReleasePowerButton();
 
   ExpectPreLockAnimationStarted();
 
   test_animator_->CompleteAllAnimations(true);
   EXPECT_EQ(1, session_manager_client_->request_lock_screen_call_count());
 }
 
 }  // namespace test
 }  // namespace ash