Shell: Move DisplayManager initialization to a separate method

This CL:
* Moves a bunch of related DisplayManager and DisplayConfigurator
  code to a separate InitializeDisplayManager method to help improve
  managability of Shell::Init.
* Renames ShutdownObserver -> DisplayShutdownObserver.
* Removes unnecessary DBusThreadManager dependencies from shell.cc.
* Moves observer responsibility from Shell to ProjectingObserver

Bug: 678949
Change-Id: I07159d0562bc032f03c653beb927ab8aaf053bbc
Reviewed-on: https://chromium-review.googlesource.com/833500Reviewed-by: Scott Violet <sky@chromium.org>
Reviewed-by: James Cook <jamescook@chromium.org>
Commit-Queue: Steven Bennetts <stevenjb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#526741}

ash/BUILD.gn

@@ -108,6 +108,8 @@ component("ash") {
     "display/display_error_observer_chromeos.h",
     "display/display_move_window_util.cc",
     "display/display_move_window_util.h",
+    "display/display_shutdown_observer.cc",
+    "display/display_shutdown_observer.h",
     "display/display_synchronizer.cc",
     "display/display_synchronizer.h",
     "display/display_util.cc",
@@ -139,8 +141,6 @@ component("ash") {
     "display/screen_position_controller.h",
     "display/shared_display_edge_indicator.cc",
     "display/shared_display_edge_indicator.h",
-    "display/shutdown_observer_chromeos.cc",
-    "display/shutdown_observer_chromeos.h",
     "display/touch_calibrator_controller.cc",
     "display/touch_calibrator_controller.h",
     "display/touch_calibrator_view.cc",

ash/display/shutdown_observer_chromeos.cc → ash/display/display_shutdown_observer.cc

@@ -2,22 +2,22 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ash/display/shutdown_observer_chromeos.h"
+#include "ash/display/display_shutdown_observer.h"
 
 #include "ui/display/manager/chromeos/display_configurator.h"
 
 namespace ash {
 
-ShutdownObserver::ShutdownObserver(
+DisplayShutdownObserver::DisplayShutdownObserver(
     display::DisplayConfigurator* display_configurator)
     : display_configurator_(display_configurator),
       scoped_session_observer_(this) {}
 
-ShutdownObserver::~ShutdownObserver() = default;
+DisplayShutdownObserver::~DisplayShutdownObserver() = default;
 
-void ShutdownObserver::OnChromeTerminating() {
+void DisplayShutdownObserver::OnChromeTerminating() {
   // Stop handling display configuration events once the shutdown
-  // process starts. crbug.com/177014.
+  // process starts. http://crbug.com/177014.
   display_configurator_->PrepareForExit();
 }
 

ash/display/shutdown_observer_chromeos.h → ash/display/display_shutdown_observer.h

@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef ASH_DISPLAY_SHUTDOWN_OBSERVER_CHROMEOS_H_
-#define ASH_DISPLAY_SHUTDOWN_OBSERVER_CHROMEOS_H_
+#ifndef ASH_DISPLAY_DISPLAY_SHUTDOWN_OBSERVER_H_
+#define ASH_DISPLAY_DISPLAY_SHUTDOWN_OBSERVER_H_
 
 #include "ash/session/session_observer.h"
 #include "base/macros.h"
@@ -16,10 +16,11 @@ namespace ash {
 
 // Adds self as SessionObserver and listens for OnChromeTerminating() on
 // behalf of |display_configurator_|.
-class ShutdownObserver : public SessionObserver {
+class DisplayShutdownObserver : public SessionObserver {
  public:
-  explicit ShutdownObserver(display::DisplayConfigurator* display_configurator);
-  ~ShutdownObserver() override;
+  explicit DisplayShutdownObserver(
+      display::DisplayConfigurator* display_configurator);
+  ~DisplayShutdownObserver() override;
 
  private:
   // SessionObserver:
@@ -28,9 +29,9 @@ class ShutdownObserver : public SessionObserver {
   display::DisplayConfigurator* const display_configurator_;
   ScopedSessionObserver scoped_session_observer_;
 
-  DISALLOW_COPY_AND_ASSIGN(ShutdownObserver);
+  DISALLOW_COPY_AND_ASSIGN(DisplayShutdownObserver);
 };
 
 }  // namespace ash
 
-#endif  // ASH_DISPLAY_SHUTDOWN_OBSERVER_CHROMEOS_H_
+#endif  // ASH_DISPLAY_DISPLAY_SHUTDOWN_OBSERVER_H_

ash/display/projecting_observer_chromeos.cc

@@ -4,22 +4,29 @@
 
 #include "ash/display/projecting_observer_chromeos.h"
 
+#include "ash/shell.h"
 #include "base/logging.h"
+#include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/dbus/power_manager_client.h"
 #include "ui/display/types/display_snapshot.h"
 
 namespace ash {
 
 ProjectingObserver::ProjectingObserver(
-    chromeos::PowerManagerClient* power_manager_client)
-    : has_internal_output_(false),
-      output_count_(0),
-      casting_session_count_(0),
-      power_manager_client_(power_manager_client) {
-  DCHECK(power_manager_client);
+    display::DisplayConfigurator* display_configurator)
+    : display_configurator_(display_configurator) {
+  if (Shell::HasInstance())
+    Shell::Get()->AddShellObserver(this);
+  if (display_configurator_)
+    display_configurator_->AddObserver(this);
 }
 
-ProjectingObserver::~ProjectingObserver() = default;
+ProjectingObserver::~ProjectingObserver() {
+  if (Shell::HasInstance())
+    Shell::Get()->RemoveShellObserver(this);
+  if (display_configurator_)
+    display_configurator_->RemoveObserver(this);
+}
 
 void ProjectingObserver::OnDisplayModeChanged(
     const display::DisplayConfigurator::DisplayStateList& display_states) {
@@ -56,7 +63,12 @@ void ProjectingObserver::SetIsProjecting() {
   bool projecting =
       has_internal_output_ && (output_count_ + casting_session_count_ > 1);
 
-  power_manager_client_->SetIsProjecting(projecting);
+  chromeos::PowerManagerClient* power_manager_client =
+      power_manager_client_for_test_
+          ? power_manager_client_for_test_
+          : chromeos::DBusThreadManager::Get()->GetPowerManagerClient();
+  if (power_manager_client)
+    power_manager_client->SetIsProjecting(projecting);
 }
 
 }  // namespace ash

ash/display/projecting_observer_chromeos.h

@@ -20,9 +20,9 @@ class ASH_EXPORT ProjectingObserver
     : public display::DisplayConfigurator::Observer,
       public ShellObserver {
  public:
-  // |power_manager_client| must outlive this object.
+  // |display_configurator| must outlive this instance. May be null in tests.
   explicit ProjectingObserver(
-      chromeos::PowerManagerClient* power_manager_client);
+      display::DisplayConfigurator* display_configurator);
   ~ProjectingObserver() override;
 
   // DisplayConfigurator::Observer implementation:
@@ -33,21 +33,30 @@ class ASH_EXPORT ProjectingObserver
   void OnCastingSessionStartedOrStopped(bool started) override;
 
  private:
+  friend class ProjectingObserverTest;
+
+  void set_power_manager_client_for_test(
+      chromeos::PowerManagerClient* power_manager_client) {
+    power_manager_client_for_test_ = power_manager_client;
+  }
+
   // Sends the current projecting state to power manager.
   void SetIsProjecting();
 
+  display::DisplayConfigurator* display_configurator_;  // Unowned
+
   // True if at least one output is internal. This value is updated when
   // |OnDisplayModeChanged| is called.
-  bool has_internal_output_;
+  bool has_internal_output_ = false;
 
   // Keeps track of the number of connected outputs.
-  int output_count_;
+  int output_count_ = 0;
 
   // Number of outstanding casting sessions.
-  int casting_session_count_;
+  int casting_session_count_ = 0;
 
-  // Weak pointer to the DBusClient PowerManagerClient;
-  chromeos::PowerManagerClient* power_manager_client_;
+  // Weak pointer to the DBusClient PowerManagerClient for testing;
+  chromeos::PowerManagerClient* power_manager_client_for_test_ = nullptr;
 
   DISALLOW_COPY_AND_ASSIGN(ProjectingObserver);
 };

ash/display/projecting_observer_chromeos_unittest.cc

@@ -12,6 +12,7 @@
 #include "ui/display/manager/fake_display_snapshot.h"
 
 namespace ash {
+
 namespace {
 
 std::unique_ptr<display::DisplaySnapshot> CreateInternalSnapshot() {
@@ -30,33 +31,36 @@ std::unique_ptr<display::DisplaySnapshot> CreateVGASnapshot() {
       .Build();
 }
 
+display::DisplayConfigurator::DisplayStateList GetPointers(
+    const std::vector<std::unique_ptr<display::DisplaySnapshot>>& displays) {
+  display::DisplayConfigurator::DisplayStateList result;
+  for (const auto& display : displays)
+    result.push_back(display.get());
+  return result;
+}
+
+}  // namespace
+
 class ProjectingObserverTest : public testing::Test {
  public:
-  ProjectingObserverTest() : observer_(&fake_power_client_) {}
+  ProjectingObserverTest() {
+    observer_ = std::make_unique<ProjectingObserver>(nullptr);
+    observer_->set_power_manager_client_for_test(&fake_power_client_);
+  }
 
   ~ProjectingObserverTest() override = default;
 
  protected:
   chromeos::FakePowerManagerClient fake_power_client_;
-  ProjectingObserver observer_;
+  std::unique_ptr<ProjectingObserver> observer_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(ProjectingObserverTest);
 };
 
-display::DisplayConfigurator::DisplayStateList GetPointers(
-    const std::vector<std::unique_ptr<display::DisplaySnapshot>>& displays) {
-  display::DisplayConfigurator::DisplayStateList result;
-  for (const auto& display : displays)
-    result.push_back(display.get());
-  return result;
-}
-
-}  // namespace
-
 TEST_F(ProjectingObserverTest, CheckNoDisplay) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(1, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_FALSE(fake_power_client_.is_projecting());
@@ -65,7 +69,7 @@ TEST_F(ProjectingObserverTest, CheckNoDisplay) {
 TEST_F(ProjectingObserverTest, CheckWithoutInternalDisplay) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateVGASnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(1, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_FALSE(fake_power_client_.is_projecting());
@@ -74,7 +78,7 @@ TEST_F(ProjectingObserverTest, CheckWithoutInternalDisplay) {
 TEST_F(ProjectingObserverTest, CheckWithInternalDisplay) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(1, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_FALSE(fake_power_client_.is_projecting());
@@ -84,7 +88,7 @@ TEST_F(ProjectingObserverTest, CheckWithTwoVGADisplays) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateVGASnapshot());
   displays.push_back(CreateVGASnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(1, fake_power_client_.num_set_is_projecting_calls());
   // We need at least 1 internal display to set projecting to on.
@@ -95,7 +99,7 @@ TEST_F(ProjectingObserverTest, CheckWithInternalAndVGADisplays) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
   displays.push_back(CreateVGASnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(1, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_TRUE(fake_power_client_.is_projecting());
@@ -104,9 +108,9 @@ TEST_F(ProjectingObserverTest, CheckWithInternalAndVGADisplays) {
 TEST_F(ProjectingObserverTest, CheckWithVGADisplayAndOneCastingSession) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateVGASnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
-  observer_.OnCastingSessionStartedOrStopped(true);
+  observer_->OnCastingSessionStartedOrStopped(true);
 
   EXPECT_EQ(2, fake_power_client_.num_set_is_projecting_calls());
   // Need at least one internal display to set projecting state to |true|.
@@ -116,9 +120,9 @@ TEST_F(ProjectingObserverTest, CheckWithVGADisplayAndOneCastingSession) {
 TEST_F(ProjectingObserverTest, CheckWithInternalDisplayAndOneCastingSession) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
-  observer_.OnCastingSessionStartedOrStopped(true);
+  observer_->OnCastingSessionStartedOrStopped(true);
 
   EXPECT_EQ(2, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_TRUE(fake_power_client_.is_projecting());
@@ -127,15 +131,15 @@ TEST_F(ProjectingObserverTest, CheckWithInternalDisplayAndOneCastingSession) {
 TEST_F(ProjectingObserverTest, CheckProjectingAfterClosingACastingSession) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
-  observer_.OnCastingSessionStartedOrStopped(true);
-  observer_.OnCastingSessionStartedOrStopped(true);
+  observer_->OnCastingSessionStartedOrStopped(true);
+  observer_->OnCastingSessionStartedOrStopped(true);
 
   EXPECT_EQ(3, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_TRUE(fake_power_client_.is_projecting());
 
-  observer_.OnCastingSessionStartedOrStopped(false);
+  observer_->OnCastingSessionStartedOrStopped(false);
 
   EXPECT_EQ(4, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_TRUE(fake_power_client_.is_projecting());
@@ -145,10 +149,10 @@ TEST_F(ProjectingObserverTest,
        CheckStopProjectingAfterClosingAllCastingSessions) {
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
-  observer_.OnCastingSessionStartedOrStopped(true);
-  observer_.OnCastingSessionStartedOrStopped(false);
+  observer_->OnCastingSessionStartedOrStopped(true);
+  observer_->OnCastingSessionStartedOrStopped(false);
 
   EXPECT_EQ(3, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_FALSE(fake_power_client_.is_projecting());
@@ -159,11 +163,11 @@ TEST_F(ProjectingObserverTest,
   std::vector<std::unique_ptr<display::DisplaySnapshot>> displays;
   displays.push_back(CreateInternalSnapshot());
   displays.push_back(CreateVGASnapshot());
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   // Remove VGA output.
   displays.erase(displays.begin() + 1);
-  observer_.OnDisplayModeChanged(GetPointers(displays));
+  observer_->OnDisplayModeChanged(GetPointers(displays));
 
   EXPECT_EQ(2, fake_power_client_.num_set_is_projecting_calls());
   EXPECT_FALSE(fake_power_client_.is_projecting());

ash/shell.cc

@@ -25,6 +25,7 @@
 #include "ash/display/display_color_manager_chromeos.h"
 #include "ash/display/display_configuration_controller.h"
 #include "ash/display/display_error_observer_chromeos.h"
+#include "ash/display/display_shutdown_observer.h"
 #include "ash/display/event_transformation_handler.h"
 #include "ash/display/mouse_cursor_event_filter.h"
 #include "ash/display/projecting_observer_chromeos.h"
@@ -32,7 +33,6 @@
 #include "ash/display/screen_ash.h"
 #include "ash/display/screen_orientation_controller_chromeos.h"
 #include "ash/display/screen_position_controller.h"
-#include "ash/display/shutdown_observer_chromeos.h"
 #include "ash/display/window_tree_host_manager.h"
 #include "ash/drag_drop/drag_drop_controller.h"
 #include "ash/first_run/first_run_helper_impl.h"
@@ -141,7 +141,6 @@
 #include "base/threading/sequenced_worker_pool.h"
 #include "base/trace_event/trace_event.h"
 #include "chromeos/chromeos_switches.h"
-#include "chromeos/dbus/dbus_thread_manager.h"
 #include "chromeos/system/devicemode.h"
 #include "components/prefs/pref_registry_simple.h"
 #include "components/prefs/pref_service.h"
@@ -786,22 +785,17 @@ Shell::~Shell() {
   screen_position_controller_.reset();
 
   display_color_manager_.reset();
+  projecting_observer_.reset();
+
   if (display_change_observer_)
     display_configurator_->RemoveObserver(display_change_observer_.get());
   if (display_error_observer_)
     display_configurator_->RemoveObserver(display_error_observer_.get());
-  if (projecting_observer_) {
-    display_configurator_->RemoveObserver(projecting_observer_.get());
-    RemoveShellObserver(projecting_observer_.get());
-  }
   display_change_observer_.reset();
-  shutdown_observer_.reset();
+  display_shutdown_observer_.reset();
 
   PowerStatus::Shutdown();
 
-  // Ensure that DBusThreadManager outlives this Shell.
-  DCHECK(chromeos::DBusThreadManager::IsInitialized());
-
   // Needs to happen right before |instance_| is reset.
   shell_port_.reset();
   session_controller_->RemoveObserver(this);
@@ -881,65 +875,19 @@ void Shell::Init(ui::ContextFactory* context_factory,
         base::WrapUnique(native_cursor_manager_));
   }
 
+  // TODO(stevenjb): ChromeShellDelegate::PreInit currently handles
+  // DisplayPreference initialization, required for InitializeDisplayManager.
+  // Before we can move that code into ash/display where it belongs, we need to
+  // wait for |lcoal_state_| to be set in OnLocalStatePrefServiceInitialized
+  // before initializing DisplayPreferences (and therefore DisplayManager).
+  // http://crbug.com/678949.
   shell_delegate_->PreInit();
-  bool display_initialized = display_manager_->InitFromCommandLine();
-  if (!display_initialized && config != Config::CLASSIC) {
-    // Run display configuration off device in mus mode.
-    display_manager_->set_configure_displays(true);
-    display_configurator_->set_configure_display(true);
-  }
-  display_configuration_controller_ =
-      std::make_unique<DisplayConfigurationController>(
-          display_manager_.get(), window_tree_host_manager_.get());
-  display_configurator_->Init(shell_port_->CreateNativeDisplayDelegate(),
-                              false);
-
-  // The DBusThreadManager must outlive this Shell. See the DCHECK in ~Shell.
-  chromeos::DBusThreadManager* dbus_thread_manager =
-      chromeos::DBusThreadManager::Get();
-  projecting_observer_.reset(
-      new ProjectingObserver(dbus_thread_manager->GetPowerManagerClient()));
-  display_configurator_->AddObserver(projecting_observer_.get());
-  AddShellObserver(projecting_observer_.get());
-
-  if (!display_initialized) {
-    if (config != Config::CLASSIC && !chromeos::IsRunningAsSystemCompositor()) {
-      display::mojom::DevDisplayControllerPtr controller;
-      shell_delegate_->GetShellConnector()->BindInterface(
-          ui::mojom::kServiceName, &controller);
-      display_manager_->SetDevDisplayController(std::move(controller));
-    }
-
-    if (config != Config::CLASSIC || chromeos::IsRunningAsSystemCompositor()) {
-      display_change_observer_ =
-          std::make_unique<display::DisplayChangeObserver>(
-              display_configurator_.get(), display_manager_.get());
 
-      shutdown_observer_ =
-          std::make_unique<ShutdownObserver>(display_configurator_.get());
-
-      // Register |display_change_observer_| first so that the rest of
-      // observer gets invoked after the root windows are configured.
-      display_configurator_->AddObserver(display_change_observer_.get());
-      display_error_observer_.reset(new DisplayErrorObserver());
-      display_configurator_->AddObserver(display_error_observer_.get());
-      display_configurator_->set_state_controller(
-          display_change_observer_.get());
-      display_configurator_->set_mirroring_controller(display_manager_.get());
-      display_configurator_->ForceInitialConfigure();
-      display_initialized = true;
-    }
-  }
-
-  display_color_manager_ =
-      std::make_unique<DisplayColorManager>(display_configurator_.get());
-
-  if (!display_initialized)
-    display_manager_->InitDefaultDisplay();
+  InitializeDisplayManager();
 
   if (config == Config::CLASSIC) {
-    display_manager_->RefreshFontParams();
-
+    // This will initialize aura::Env which requires |display_manager_| to
+    // be initialized first.
     aura::Env::GetInstance()->set_context_factory(context_factory);
     aura::Env::GetInstance()->set_context_factory_private(
         context_factory_private);
@@ -1161,6 +1109,63 @@ void Shell::Init(ui::ContextFactory* context_factory,
   user_metrics_recorder_->OnShellInitialized();
 }
 
+void Shell::InitializeDisplayManager() {
+  const Config config = shell_port_->GetAshConfig();
+  bool display_initialized = display_manager_->InitFromCommandLine();
+
+  if (!display_initialized && config != Config::CLASSIC) {
+    // Run display configuration off device in mus mode.
+    display_manager_->set_configure_displays(true);
+    display_configurator_->set_configure_display(true);
+  }
+  display_configuration_controller_ =
+      std::make_unique<DisplayConfigurationController>(
+          display_manager_.get(), window_tree_host_manager_.get());
+  display_configurator_->Init(shell_port_->CreateNativeDisplayDelegate(),
+                              false);
+
+  projecting_observer_ =
+      std::make_unique<ProjectingObserver>(display_configurator_.get());
+
+  if (!display_initialized) {
+    if (config != Config::CLASSIC && !chromeos::IsRunningAsSystemCompositor()) {
+      display::mojom::DevDisplayControllerPtr controller;
+      shell_delegate_->GetShellConnector()->BindInterface(
+          ui::mojom::kServiceName, &controller);
+      display_manager_->SetDevDisplayController(std::move(controller));
+    }
+
+    if (config != Config::CLASSIC || chromeos::IsRunningAsSystemCompositor()) {
+      display_change_observer_ =
+          std::make_unique<display::DisplayChangeObserver>(
+              display_configurator_.get(), display_manager_.get());
+
+      display_shutdown_observer_ = std::make_unique<DisplayShutdownObserver>(
+          display_configurator_.get());
+
+      // Register |display_change_observer_| first so that the rest of
+      // observer gets invoked after the root windows are configured.
+      display_configurator_->AddObserver(display_change_observer_.get());
+      display_error_observer_.reset(new DisplayErrorObserver());
+      display_configurator_->AddObserver(display_error_observer_.get());
+      display_configurator_->set_state_controller(
+          display_change_observer_.get());
+      display_configurator_->set_mirroring_controller(display_manager_.get());
+      display_configurator_->ForceInitialConfigure();
+      display_initialized = true;
+    }
+  }
+
+  display_color_manager_ =
+      std::make_unique<DisplayColorManager>(display_configurator_.get());
+
+  if (!display_initialized)
+    display_manager_->InitDefaultDisplay();
+
+  if (config == Config::CLASSIC)
+    display_manager_->RefreshFontParams();
+}
+
 void Shell::InitRootWindow(aura::Window* root_window) {
   DCHECK(focus_controller_);
   DCHECK(visibility_controller_.get());

ash/shell.h

@@ -94,6 +94,7 @@ class CastConfigController;
 class DisplayColorManager;
 class DisplayConfigurationController;
 class DisplayErrorObserver;
+class DisplayShutdownObserver;
 class DragDropController;
 class EventClientImpl;
 class EventTransformationHandler;
@@ -143,7 +144,6 @@ class ShellDelegate;
 struct ShellInitParams;
 class ShellObserver;
 class ShutdownController;
-class ShutdownObserver;
 class SmsObserver;
 class SplitViewController;
 class StickyKeysController;
@@ -588,6 +588,9 @@ class ASH_EXPORT Shell : public SessionObserver,
   void Init(ui::ContextFactory* context_factory,
             ui::ContextFactoryPrivate* context_factory_private);
 
+  // Initializes the display manager and related components.
+  void InitializeDisplayManager();
+
   // Initializes the root window so that it can host browser windows.
   void InitRootWindow(aura::Window* root_window);
 
@@ -745,7 +748,7 @@ class ASH_EXPORT Shell : public SessionObserver,
   std::unique_ptr<display::DisplayChangeObserver> display_change_observer_;
 
   // Listens for shutdown and updates DisplayConfigurator.
-  std::unique_ptr<ShutdownObserver> shutdown_observer_;
+  std::unique_ptr<DisplayShutdownObserver> display_shutdown_observer_;
 
   // Listens for new sms messages and shows notifications.
   std::unique_ptr<SmsObserver> sms_observer_;