Delay display configuration after waking up from suspend with multi displays

ui/display/chromeos/display_configurator_unittest.cc

 // Copyright 2014 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 "ui/display/chromeos/display_configurator.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
+#include "base/callback_helpers.h"
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/memory/scoped_vector.h"
 #include "base/message_loop/message_loop.h"
 #include "base/run_loop.h"
 #include "testing/gtest/include/gtest/gtest.h"
 #include "ui/display/chromeos/test/action_logger_util.h"
 #include "ui/display/chromeos/test/test_display_snapshot.h"
 #include "ui/display/chromeos/test/test_native_display_delegate.h"
 #include "ui/display/util/display_util.h"
 
 namespace ui {
 namespace test {
 
 namespace {
 
+enum CallbackResult {
+  CALLBACK_FAILURE,
+  CALLBACK_SUCCESS,
+  CALLBACK_NOT_CALLED,
+};
+
+// The delay less than which we expect the configuration to be finished.
+constexpr base::TimeDelta kMaxShortDelayMs =
+    base::TimeDelta::FromMilliseconds(
+        DisplayConfigurator::kConfigureDelayMs / 3);
+
+// The minimum configuration delay we expect when resuming while in 2+ display
+// mode.
+constexpr base::TimeDelta kMinLongDelayMs =

[Daniel Erat, 2016/10/24 16:31:04]

do these tests actually wait this long for the code to run? it looks like they
might. if so, please find a way to avoid doing this -- tests need to run quickly
and shouldn't sleep. see the existing
DisplayConfigurator::TestApi::TriggerConfigureTimeout() method used by other
tests. to test the delay before you make the timer fire, add a new method to
TestApi like:

  base::TimeDelta GetConfigureDelay() const {
    return configurator_->configure_timer_.IsRunning() ?
        configurator_->configure_timer_.GetCurrentDelay() :
        base::TimeDelta();
  }

[afakhry, 2016/10/25 00:37:10]

That's a great suggestion! The tests indeed used to wait for long durations,
which wasn't pleasant and could introduce future flakiness.

This simplifies the waiters logic a lot.
Done.

+    base::TimeDelta::FromMilliseconds(
+        DisplayConfigurator::kResumeConfigureMultiDisplayDelayMs);
+
 class TestObserver : public DisplayConfigurator::Observer {
  public:
   explicit TestObserver(DisplayConfigurator* configurator)
       : configurator_(configurator) {
     Reset();
     configurator_->AddObserver(this);
   }
   ~TestObserver() override { configurator_->RemoveObserver(this); }
 
   int num_changes() const { return num_changes_; }
@@ skipping 76 matching lines @@
   bool SoftwareMirroringEnabled() const override {
     return software_mirroring_enabled_;
   }
 
  private:
   bool software_mirroring_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(TestMirroringController);
 };
 
+// Abstracts waiting for the display configuration to be completed and getting
+// the time it took to complete.
+class ConfigurationWaiter {
+ public:
+  ConfigurationWaiter()
+      : on_configured_callback_(base::Bind(&ConfigurationWaiter::OnConfigured,
+                                           base::Unretained(this))),
+        start_(base::TimeTicks::Now()),
+        end_(base::TimeTicks::Max()),
+        callback_result_(CALLBACK_NOT_CALLED),
+        pending_configuration_(true) {
+  }
+
+  ~ConfigurationWaiter() = default;
+
+  void Reset() {
+    start_ = base::TimeTicks::Now();
+    end_ = base::TimeTicks::Max();
+    callback_result_ = CALLBACK_NOT_CALLED;
+    pending_configuration_ = true;
+  }
+
+  // Waits for the configuration to complete and returns how long it took since
+  // we created or Reset()ed the timer.
+  base::TimeDelta Wait() WARN_UNUSED_RESULT {
+    if (pending_configuration_) {
+      base::RunLoop run_loop;
+      quit_closure_ = run_loop.QuitClosure();
+      run_loop.Run();
+    }
+
+    return end_ - start_;
+  }
+
+  const DisplayConfigurator::ConfigurationCallback&
+  on_configuration_callback() const {
+    return on_configured_callback_;
+  }
+
+  CallbackResult callback_result() const { return callback_result_; }
+
+ private:
+  void OnConfigured(bool status) {
+    callback_result_ = status ? CALLBACK_SUCCESS : CALLBACK_FAILURE;
+
+    pending_configuration_ = false;
+    end_ = base::TimeTicks::Now();
+
+    if (!quit_closure_.is_null())
+      base::ResetAndReturn(&quit_closure_).Run();
+  }
+
+  // The callback that should be used with the DisplayConfigurator calls to be
+  // invoked with the display configuration is done. It will always execute this
+  // waiter's OnConfigured() to end the wait (if any) and update the timers.
+  const DisplayConfigurator::ConfigurationCallback on_configured_callback_;
+
+  // Time at which we start measuring how long display configuration took.
+  base::TimeTicks start_;
+
+  // Time at which the display configuration was complete.
+  base::TimeTicks end_;
+
+  // The quit closure of the waiter runloop.
+  base::Closure quit_closure_;
+
+  // The status of the display configuration.
+  CallbackResult callback_result_;
+
+  // True if we are expecting and waiting for a display configuration
+  // completion, false if the configuration has already been completed.
+  bool pending_configuration_;
+
+  DISALLOW_COPY_AND_ASSIGN(ConfigurationWaiter);
+};
+
 class DisplayConfiguratorTest : public testing::Test {
  public:
-  enum CallbackResult {
-    CALLBACK_FAILURE,
-    CALLBACK_SUCCESS,
-    CALLBACK_NOT_CALLED,
-  };
-
   DisplayConfiguratorTest()
       : small_mode_(gfx::Size(1366, 768), false, 60.0f),
         big_mode_(gfx::Size(2560, 1600), false, 60.0f),
         observer_(&configurator_),
         test_api_(&configurator_),
         enable_content_protection_status_(0),
         enable_content_protection_call_count_(0),
         query_content_protection_call_count_(0),
-        callback_result_(CALLBACK_NOT_CALLED),
         display_control_result_(CALLBACK_NOT_CALLED) {}
   ~DisplayConfiguratorTest() override {}
 
   void SetUp() override {
     log_.reset(new ActionLogger());
 
     native_display_delegate_ = new TestNativeDisplayDelegate(log_.get());
     configurator_.SetDelegateForTesting(
         std::unique_ptr<NativeDisplayDelegate>(native_display_delegate_));
 
@@ skipping 28 matching lines @@
     o->set_current_mode(modes.back().get());
     o->set_native_mode(modes.back().get());
     o->set_modes(std::move(modes));
     o->set_type(DISPLAY_CONNECTION_TYPE_HDMI);
     o->set_is_aspect_preserving_scaling(true);
     o->set_display_id(789);
 
     UpdateOutputs(2, false);
   }
 
-  void OnConfiguredCallback(bool status) {
-    callback_result_ = (status ? CALLBACK_SUCCESS : CALLBACK_FAILURE);
-  }
-
   void OnDisplayControlUpdated(bool status) {
     display_control_result_ = (status ? CALLBACK_SUCCESS : CALLBACK_FAILURE);
   }
 
   void EnableContentProtectionCallback(bool status) {
     enable_content_protection_status_ = status;
     enable_content_protection_call_count_++;
   }
 
   void QueryContentProtectionCallback(
@@ skipping 39 matching lines @@
     configurator_.ForceInitialConfigure(0);
     EXPECT_EQ(JoinActions(kInitXRandR, kGrab,
                           GetFramebufferAction(small_mode_.size(), &outputs_[0],
                                                NULL).c_str(),
                           GetCrtcAction(outputs_[0], &small_mode_,
                                         gfx::Point(0, 0)).c_str(),
                           kForceDPMS, kUngrab, NULL),
               log_->GetActionsAndClear());
   }
 
-  CallbackResult PopCallbackResult() {
-    CallbackResult result = callback_result_;
-    callback_result_ = CALLBACK_NOT_CALLED;
-    return result;
-  }
-
   CallbackResult PopDisplayControlResult() {
     CallbackResult result = display_control_result_;
     display_control_result_ = CALLBACK_NOT_CALLED;
     return result;
   }
 
   base::MessageLoop message_loop_;
   TestStateController state_controller_;
   TestMirroringController mirroring_controller_;
   DisplayConfigurator configurator_;
   TestObserver observer_;
   std::unique_ptr<ActionLogger> log_;
   TestNativeDisplayDelegate* native_display_delegate_;  // not owned
   DisplayConfigurator::TestApi test_api_;
 
   bool enable_content_protection_status_;
   int enable_content_protection_call_count_;
   DisplayConfigurator::QueryProtectionResponse
       query_content_protection_response_;
   int query_content_protection_call_count_;
 
   TestDisplaySnapshot outputs_[3];
 
-  CallbackResult callback_result_;
   CallbackResult display_control_result_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DisplayConfiguratorTest);
 };
 
 }  // namespace
 
 TEST_F(DisplayConfiguratorTest, FindDisplayModeMatchingSize) {
   std::vector<const DisplayMode*> modes;
@@ skipping 372 matching lines @@
           GetCrtcAction(outputs_[1], &small_mode_, gfx::Point(0, 0)).c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
   EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // Turning off the internal display should switch the external display to
   // its native mode.
   observer_.Reset();
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(big_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &big_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_SINGLE, configurator_.display_state());
   EXPECT_EQ(1, observer_.num_changes());
 
   // When all displays are turned off, the framebuffer should switch back
   // to the mirrored size.
   observer_.Reset();
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(kGrab,
                   GetFramebufferAction(
                       small_mode_.size(), &outputs_[0], &outputs_[1]).c_str(),
                   GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
                   GetCrtcAction(outputs_[1], NULL, gfx::Point(0, 0)).c_str(),
                   kUngrab,
                   NULL),
       log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR, configurator_.display_state());
   EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // Turn all displays on and check that mirroring is still used.
   observer_.Reset();
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
@@ skipping 31 matching lines @@
           NULL),
       log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
             configurator_.display_state());
   EXPECT_TRUE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // Turning off the internal display should switch the external display to
   // its native mode.
   observer_.Reset();
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(big_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &big_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_SINGLE, configurator_.display_state());
   EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // When all displays are turned off, the framebuffer should switch back
   // to the extended + software mirroring.
   observer_.Reset();
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0],
                                &outputs_[1]).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1],
                         NULL,
                         gfx::Point(0,
                                    small_mode_.size().height() +
                                        DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
   EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
             configurator_.display_state());
   EXPECT_TRUE(mirroring_controller_.SoftwareMirroringEnabled());
   EXPECT_EQ(1, observer_.num_changes());
 
   // Turn all displays on and check that mirroring is still used.
   observer_.Reset();
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0],
                                &outputs_[1]).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1],
                         &big_mode_,
                         gfx::Point(0,
@@ skipping 11 matching lines @@
 }
 
 TEST_F(DisplayConfiguratorTest, SuspendAndResume) {
   InitWithSingleOutput();
 
   // No preparation is needed before suspending when the display is already
   // on.  The configurator should still reprobe on resume in case a display
   // was connected while suspended.
   const gfx::Size framebuffer_size = configurator_.framebuffer_size();
   DCHECK(!framebuffer_size.IsEmpty());
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  ConfigurationWaiter config_waiter;
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(framebuffer_size.ToString(),
             configurator_.framebuffer_size().ToString());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           kSync,
           NULL),
       log_->GetActionsAndClear());
-  configurator_.ResumeDisplays();
+
+  // No resume delay in single display mode.
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
   // Now turn the display off before suspending and check that the
   // configurator turns it back on and syncs with the server.
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(kSync, log_->GetActionsAndClear());
 
-  configurator_.ResumeDisplays();
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR);
   UpdateOutputs(2, true);
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &small_mode_, gfx::Point(0, 0)).c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR,
+            configurator_.display_state());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  // No delay in suspend.
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_OFF,
+            configurator_.current_power_state());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR,
+            configurator_.display_state());
   EXPECT_EQ(kSync, log_->GetActionsAndClear());
 
   // If a display is disconnected while suspended, the configurator should
-  // pick up the change and only turn on the internal display.
+  // pick up the change and only turn on the internal display. The should be
+  // a longer configuration delay when we set the displays back to on.
   UpdateOutputs(1, false);
-  configurator_.ResumeDisplays();
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
+      config_waiter.on_configuration_callback());
+  EXPECT_GE(config_waiter.Wait(), kMinLongDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 }
 
 TEST_F(DisplayConfiguratorTest, Headless) {
   UpdateOutputs(0, false);
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
   Init(false);
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
   configurator_.ForceInitialConfigure(0);
   EXPECT_EQ(JoinActions(kInitXRandR, kGrab, kForceDPMS, kUngrab, NULL),
             log_->GetActionsAndClear());
 
   // Not much should happen when the display power state is changed while
   // no displays are connected.
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(JoinActions(kGrab, kUngrab, NULL), log_->GetActionsAndClear());
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(JoinActions(kGrab, kForceDPMS, kUngrab, NULL),
             log_->GetActionsAndClear());
 
   // Connect an external display and check that it's configured correctly.
   std::vector<std::unique_ptr<const DisplayMode>> modes;
   for (const std::unique_ptr<const DisplayMode>& mode : outputs_[1].modes()) {
     modes.push_back(mode->Clone());
     if (mode.get() == outputs_[1].current_mode())
       outputs_[0].set_current_mode(modes.back().get());
     if (mode.get() == outputs_[1].native_mode())
@@ skipping 223 matching lines @@
             log_->GetActionsAndClear());
 }
 
 TEST_F(DisplayConfiguratorTest, DoNotConfigureWithSuspendedDisplays) {
   InitWithSingleOutput();
 
   // The DisplayConfigurator may occasionally receive OnConfigurationChanged()
   // after the displays have been suspended.  This event should be ignored since
   // the DisplayConfigurator will force a probe and reconfiguration of displays
   // at resume time.
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  ConfigurationWaiter config_waiter;
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           kSync,
           NULL),
       log_->GetActionsAndClear());
 
   // The configuration timer should not be started when the displays
   // are suspended.
   configurator_.OnConfigurationChanged();
   EXPECT_FALSE(test_api_.TriggerConfigureTimeout());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 
   // Calls to SetDisplayPower should do nothing if the power state doesn't
   // change.
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
@@ skipping 13 matching lines @@
   // The DisplayConfigurator should do nothing at resume time if there is no
   // state change.
   UpdateOutputs(1, false);
   configurator_.ResumeDisplays();
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 
   // If a configuration task is pending when the displays are suspended, that
   // task should not run either and the timer should be stopped. The displays
   // should be turned off by suspend.
   configurator_.OnConfigurationChanged();
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], NULL).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           kSync,
           NULL),
       log_->GetActionsAndClear());
 
@@ skipping 208 matching lines @@
 // so they can be reused later: http://crosbug.com/p/31571
 TEST_F(DisplayConfiguratorTest, SaveDisplayPowerStateOnConfigFailure) {
   // Start out with two displays in extended mode.
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
   Init(false);
   configurator_.ForceInitialConfigure(0);
   log_->GetActionsAndClear();
   observer_.Reset();
 
   // Turn off the internal display, simulating docked mode.
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(1, observer_.num_changes());
   EXPECT_EQ(0, observer_.num_failures());
   log_->GetActionsAndClear();
 
   // Make all subsequent configuration requests fail and try to turn the
   // internal display back on.
   native_display_delegate_->set_max_configurable_pixels(1);
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_FAILURE, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_FAILURE, config_waiter.callback_result());
   EXPECT_EQ(1, observer_.num_changes());
   EXPECT_EQ(1, observer_.num_failures());
   log_->GetActionsAndClear();
 
   // Simulate the external display getting disconnected and check that the
   // internal display is turned on (i.e. DISPLAY_POWER_ALL_ON is used) rather
   // than the earlier DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON state.
   native_display_delegate_->set_max_configurable_pixels(0);
   UpdateOutputs(1, true);
   EXPECT_EQ(JoinActions(kGrab, GetFramebufferAction(small_mode_.size(),
                                                     &outputs_[0], NULL).c_str(),
                         GetCrtcAction(outputs_[0], &small_mode_,
                                       gfx::Point(0, 0)).c_str(),
                         kForceDPMS, kUngrab, NULL),
             log_->GetActionsAndClear());
 }
 
 // Tests that the SetDisplayPowerState() task posted by HandleResume() doesn't
 // use a stale state if a new state is requested before it runs:
 // http://crosbug.com/p/32393
 TEST_F(DisplayConfiguratorTest, DontRestoreStalePowerStateAfterResume) {
   // Start out with two displays in mirrored mode.
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_MIRROR);
   Init(false);
   configurator_.ForceInitialConfigure(0);
   log_->GetActionsAndClear();
   observer_.Reset();
 
   // Turn off the internal display, simulating docked mode.
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_INTERNAL_OFF_EXTERNAL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(1, observer_.num_changes());
   EXPECT_EQ(0, observer_.num_failures());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(big_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &big_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
   // Suspend and resume the system. Resuming should restore the previous power
   // state and force a probe. Suspend should turn off the displays since an
   // external monitor is connected.
-  configurator_.SuspendDisplays(base::Bind(
-      &DisplayConfiguratorTest::OnConfiguredCallback, base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(2, observer_.num_changes());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0],
               &outputs_[1]).c_str(),
           GetCrtcAction(outputs_[0], NULL, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], NULL, gfx::Point(0, 0)).c_str(),
           kUngrab,
           kSync,
           NULL),
       log_->GetActionsAndClear());
 
   // Before the task runs, exit docked mode.
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(3, observer_.num_changes());
   EXPECT_EQ(0, observer_.num_failures());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(small_mode_.size(), &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &small_mode_, gfx::Point(0, 0)).c_str(),
           kForceDPMS,
           kUngrab,
           NULL),
       log_->GetActionsAndClear());
 
   // Check that the display states are not changed after resuming.
-  configurator_.ResumeDisplays();
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
+            configurator_.current_power_state());
   EXPECT_EQ(kNoActions, log_->GetActionsAndClear());
 }
 
 TEST_F(DisplayConfiguratorTest, ExternalControl) {
   InitWithSingleOutput();
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_SINGLE);
   configurator_.RelinquishControl(
       base::Bind(&DisplayConfiguratorTest::OnDisplayControlUpdated,
                  base::Unretained(this)));
   EXPECT_EQ(CALLBACK_SUCCESS, PopDisplayControlResult());
@@ skipping 19 matching lines @@
        SetDisplayPowerWhilePendingConfigurationTaskRunning) {
   // Start out with two displays in extended mode.
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
   Init(false);
   configurator_.ForceInitialConfigure(0);
   log_->GetActionsAndClear();
   observer_.Reset();
 
   native_display_delegate_->set_run_async(true);
 
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
+      config_waiter.on_configuration_callback());
 
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
+      config_waiter.on_configuration_callback());
 
-  EXPECT_EQ(CALLBACK_NOT_CALLED, PopCallbackResult());
-  base::RunLoop().RunUntilIdle();
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  EXPECT_EQ(CALLBACK_NOT_CALLED, config_waiter.callback_result());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(1, observer_.num_changes());
   EXPECT_EQ(0, observer_.num_failures());
 
   const int kDualHeight = small_mode_.size().height() +
                           DisplayConfigurator::kVerticalGap +
                           big_mode_.size().height();
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], nullptr, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], nullptr,
                         gfx::Point(0, small_mode_.size().height() +
                                           DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab, NULL),
       log_->GetActionsAndClear());
 
+  config_waiter.Reset();
   EXPECT_TRUE(test_api_.TriggerConfigureTimeout());
-  base::RunLoop().RunUntilIdle();
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(2, observer_.num_changes());
   EXPECT_EQ(0, observer_.num_failures());
 
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
@@ skipping 10 matching lines @@
   // Start out with two displays in extended mode.
   state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
   Init(false);
   configurator_.ForceInitialConfigure(0);
   log_->GetActionsAndClear();
   observer_.Reset();
 
   // Fail display configuration.
   native_display_delegate_->set_max_configurable_pixels(-1);
 
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-
-  EXPECT_EQ(CALLBACK_FAILURE, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+    EXPECT_EQ(CALLBACK_FAILURE, config_waiter.callback_result());
   EXPECT_EQ(0, observer_.num_changes());
   EXPECT_EQ(1, observer_.num_failures());
 
   const int kDualHeight = small_mode_.size().height() +
                           DisplayConfigurator::kVerticalGap +
                           big_mode_.size().height();
 
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], nullptr, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], nullptr,
                         gfx::Point(0, small_mode_.size().height() +
                                           DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab, NULL),
       log_->GetActionsAndClear());
 
   // This configuration should trigger a display configuration since the
   // previous configuration failed.
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
 
   EXPECT_EQ(0, observer_.num_changes());
   EXPECT_EQ(2, observer_.num_failures());
   EXPECT_EQ(
       JoinActions(
           kGrab,
           GetFramebufferAction(gfx::Size(big_mode_.size().width(), kDualHeight),
                                &outputs_[0], &outputs_[1])
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
@@ skipping 65 matching lines @@
           GetCrtcAction(
               outputs_[2], &small_mode_,
               gfx::Point(0, small_mode_.size().height() +
                                 big_mode_.size().height() +
                                 2 * DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab, NULL),
       log_->GetActionsAndClear());
 
   // Verify that turning the power off works.
+  ConfigurationWaiter config_waiter;
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_OFF,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab, GetFramebufferAction(
                      gfx::Size(big_mode_.size().width(), kTripleHeight),
                      &outputs_[0], &outputs_[1])
                      .c_str(),
           GetCrtcAction(outputs_[0], nullptr, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], nullptr,
                         gfx::Point(0, small_mode_.size().height() +
                                           DisplayConfigurator::kVerticalGap))
               .c_str(),
           GetCrtcAction(
               outputs_[2], nullptr,
               gfx::Point(0, small_mode_.size().height() +
                                 big_mode_.size().height() +
                                 2 * DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab, NULL),
       log_->GetActionsAndClear());
 
+  config_waiter.Reset();
   configurator_.SetDisplayPower(
       chromeos::DISPLAY_POWER_ALL_ON,
       DisplayConfigurator::kSetDisplayPowerNoFlags,
-      base::Bind(&DisplayConfiguratorTest::OnConfiguredCallback,
-                 base::Unretained(this)));
-
-  EXPECT_EQ(CALLBACK_SUCCESS, PopCallbackResult());
+      config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
   EXPECT_EQ(
       JoinActions(
           kGrab, GetFramebufferAction(
                      gfx::Size(big_mode_.size().width(), kTripleHeight),
                      &outputs_[0], &outputs_[1])
                      .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &big_mode_,
                         gfx::Point(0, small_mode_.size().height() +
                                           DisplayConfigurator::kVerticalGap))
@@ skipping 19 matching lines @@
               .c_str(),
           GetCrtcAction(outputs_[0], &small_mode_, gfx::Point(0, 0)).c_str(),
           GetCrtcAction(outputs_[1], &big_mode_,
                         gfx::Point(0, small_mode_.size().height() +
                                           DisplayConfigurator::kVerticalGap))
               .c_str(),
           kUngrab, NULL),
       log_->GetActionsAndClear());
 }
 
+// Tests the suspend and resume behavior when in dual or multi display modes.
+TEST_F(DisplayConfiguratorTest, SuspendResumeWithMultipleDisplays) {
+  InitWithSingleOutput();
+  state_controller_.set_state(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED);
+  observer_.Reset();
+  UpdateOutputs(2, true);
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
+            configurator_.display_state());
+  EXPECT_FALSE(mirroring_controller_.SoftwareMirroringEnabled());
+  EXPECT_EQ(1, observer_.num_changes());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
+            configurator_.current_power_state());
+
+  // Suspending displays should result in an immediate configuration without
+  // delays, even in dual display mode.
+  ConfigurationWaiter config_waiter;
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_OFF,
+            configurator_.current_power_state());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
+            configurator_.display_state());
+
+  // Resuming from suspend with dual displays, should be done after a delay, and
+  // after the configuration we should still expect to be in a dual display
+  // mode.
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_GE(config_waiter.Wait(), kMinLongDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
+            configurator_.current_power_state());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
+            configurator_.display_state());
+
+  // Suspend displays and disconnect one of them while in suspend.
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_DUAL_EXTENDED,
+            configurator_.display_state());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_OFF,
+            configurator_.current_power_state());
+  UpdateOutputs(1, false);
+
+  // Now resume, and expect that we'll still have a long delay since we were in
+  // dual mode before suspend. The configurator should pick up the change and
+  // detect that we are in single display mode now.
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_GE(config_waiter.Wait(), kMinLongDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
+            configurator_.current_power_state());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_SINGLE, configurator_.display_state());
+
+  // Verify that the above is the exact same behavior for 3+ displays.
+  UpdateOutputs(3, true);
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_MULTI_EXTENDED,
+            configurator_.display_state());
+  // Suspend.
+  config_waiter.Reset();
+  configurator_.SuspendDisplays(config_waiter.on_configuration_callback());
+  EXPECT_LT(config_waiter.Wait(), kMaxShortDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_MULTI_EXTENDED,
+            configurator_.display_state());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_OFF,
+            configurator_.current_power_state());
+
+  // Resume and expect the correct delay.
+  config_waiter.Reset();
+  configurator_.ResumeDisplaysWithCallback(
+      config_waiter.on_configuration_callback());
+  EXPECT_GE(config_waiter.Wait(), kMinLongDelayMs);
+  EXPECT_EQ(CALLBACK_SUCCESS, config_waiter.callback_result());
+  EXPECT_EQ(chromeos::DISPLAY_POWER_ALL_ON,
+            configurator_.current_power_state());
+  EXPECT_EQ(MULTIPLE_DISPLAY_STATE_MULTI_EXTENDED,
+            configurator_.display_state());
+}
+
 }  // namespace test
 }  // namespace ui