Add display task to trigger display configuration

ui/display/chromeos/update_display_configuration_task.h

Index: ui/display/chromeos/update_display_configuration_task.h
diff --git a/ui/display/chromeos/update_display_configuration_task.h b/ui/display/chromeos/update_display_configuration_task.h
new file mode 100644
index 0000000000000000000000000000000000000000..2ce0ad8cac4b794bfeacca88552f67b81f393824
--- /dev/null
+++ b/ui/display/chromeos/update_display_configuration_task.h
@@ -0,0 +1,105 @@
+// 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.
+
+#ifndef UI_DISPLAY_CHROMEOS_UPDATE_DISPLAY_CONFIGURATION_TASK_H_
+#define UI_DISPLAY_CHROMEOS_UPDATE_DISPLAY_CONFIGURATION_TASK_H_
+
+#include <vector>
+
+#include "base/memory/weak_ptr.h"
+#include "ui/display/chromeos/configure_displays_task.h"
+#include "ui/display/chromeos/display_configurator.h"
+
+namespace ui {
+
+class DisplaySnapshot;
+class NativeDisplayDelegate;
+
+class DISPLAY_EXPORT UpdateDisplayConfigurationTask {
+ public:
+  typedef base::Callback<void(
+      bool /* success */,
+      const std::vector<DisplayConfigurator::DisplayState>& /* displays */,
+      const gfx::Size& /* framebuffer_size */,
+      MultipleDisplayState /* new_display_state */,
+      chromeos::DisplayPowerState /* new_power_state */)> ResponseCallback;
+
+  UpdateDisplayConfigurationTask(
+      NativeDisplayDelegate* delegate,
+      DisplayConfigurator::DisplayLayoutManager* layout_manager,
+      MultipleDisplayState new_display_state,
+      chromeos::DisplayPowerState new_power_state,
+      int power_flags,
+      uint32_t background_color_argb,
+      bool force_configure,
+      const ResponseCallback& callback);
+  ~UpdateDisplayConfigurationTask();
+
+  void Run();
+
+ private:
+  // Callback to NativeDisplayDelegate::GetDisplays().
+  void OnDisplaysUpdated(const std::vector<DisplaySnapshot*>& displays);
+
+  // Callback to ConfigureDisplaysTask used to process the result of a display
+  // configuration run.
+  void OnStateEntered(ConfigureDisplaysTask::Status status);
+
+  // If the initial display configuration run failed due to errors entering
+  // mirror more, another configuration run is executed to enter software
+  // mirroring. This is the callback used to process the result of that
+  // configuration.
+  void OnEnableSoftwareMirroring(ConfigureDisplaysTask::Status status);
+
+  // Starts the configuration process. |callback| is used to continue the task
+  // after |configure_taks_| finishes executing.
+  void EnterState(const ConfigureDisplaysTask::ResponseCallback& callback);
+
+  // Finishes display configuration and runs |callback_|.
+  void FinishConfiguration(bool success);
+
+  // Returns true if the DPMS state should be force to on.
+  bool ShouldForceDpms() const;
+
+  // Returns true if a display configuration is required.
+  bool ShouldConfigure() const;
+
+  // Returns a display state based on the power state.
+  MultipleDisplayState ChooseDisplayState() const;
+
+  NativeDisplayDelegate* delegate_;                            // Not owned.
+  DisplayConfigurator::DisplayLayoutManager* layout_manager_;  // Not owned.
+
+  // Requested display state.
+  MultipleDisplayState new_display_state_;
+
+  // Requested power state.
+  chromeos::DisplayPowerState new_power_state_;
+
+  int power_flags_;

[Daniel Erat, 2014/12/11 23:34:07]

nit: either document the flags here or point at the place where they are
documented

+
+  uint32_t background_color_argb_;
+
+  bool force_configure_;
+
+  // Used to signal that the task has finished.
+  ResponseCallback callback_;
+
+  bool force_dpms_;
+
+  // List of updated displays.
+  std::vector<DisplayConfigurator::DisplayState> cached_displays_;
+
+  gfx::Size framebuffer_size_;
+
+  scoped_ptr<ConfigureDisplaysTask> configure_task_;
+
+  base::WeakPtrFactory<UpdateDisplayConfigurationTask> weak_ptr_factory_;
+
+  DISALLOW_COPY_AND_ASSIGN(UpdateDisplayConfigurationTask);
+};
+
+}  // namespace ui
+
+#endif  // UI_DISPLAY_CHROMEOS_UPDATE_DISPLAY_CONFIGURATION_TASK_H_