Add FakeDisplayDelegate for off device usage.

ui/display/fake_display_delegate.h

Index: ui/display/fake_display_delegate.h
diff --git a/ui/display/fake_display_delegate.h b/ui/display/fake_display_delegate.h
new file mode 100644
index 0000000000000000000000000000000000000000..170c51d3de47ec4379e63221cb891d61677b2492
--- /dev/null
+++ b/ui/display/fake_display_delegate.h
@@ -0,0 +1,108 @@
+// Copyright 2016 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_FAKE_DISPLAY_DELEGATE_H_
+#define UI_DISPLAY_FAKE_DISPLAY_DELEGATE_H_
+
+#include <memory>
+#include <vector>
+
+#include "base/macros.h"
+#include "base/observer_list.h"
+#include "ui/display/display_export.h"
+#include "ui/display/fake_display_snapshot.h"
+#include "ui/display/types/fake_display_controller.h"
+#include "ui/display/types/native_display_delegate.h"
+
+namespace display {
+
+// A NativeDisplayDelegate implementation that manages fake displays. Fake
+// displays mimic physical displays but do not actually exist. This is because
+// Chrome OS does not take over the entire display when running off device and
+// instead runs inside windows provided by the parent OS. Fake displays allow us
+// to simulate different connected display states off device and to test display
+// configuration and display management code.
+//
+// The size and number of displays can controlled via --display-config=X
+// command line flag with the format:
+//   HxW[,]
+//     H: display height in pixels
+//     W: display width in pixels
+//
+// Two 800x800 displays:
+//  --display-config=800x800,800x800

[rjkroege, 2016/09/15 00:52:46]

This is a screen config yes? I'd like us to follow the mostly standard
nomenclature.

A NativeDisplayDelegate is mis-named. It should be a NativeScreenDelegate. But
we've not done that yet.

[kylechar, 2016/09/15 17:31:55]

sgtm, changed to --screen-config.

+// One 1820x1080 display and one 400x400 display:
+//  --display-config=1920x1080,400x400
+//
+// FakeDisplayDelegate also implements FakeDisplayController which provides a
+// way to change the display state at runtime.
+class DISPLAY_EXPORT FakeDisplayDelegate : public ui::NativeDisplayDelegate,
+                                           public FakeDisplayController {
+ public:
+  FakeDisplayDelegate();
+  ~FakeDisplayDelegate() override;
+
+  // FakeDisplayController:
+  int64_t AddDisplay(const gfx::Size& display_size) override;
+  bool RemoveDisplay(int64_t display_id) override;
+
+  // NativeDisplayDelegate overrides:
+  void Initialize() override;
+  void GrabServer() override;
+  void UngrabServer() override;
+  void TakeDisplayControl(const ui::DisplayControlCallback& callback) override;
+  void RelinquishDisplayControl(
+      const ui::DisplayControlCallback& callback) override;
+  void SyncWithServer() override;
+  void SetBackgroundColor(uint32_t color_argb) override;
+  void ForceDPMSOn() override;
+  void GetDisplays(const ui::GetDisplaysCallback& callback) override;
+  void AddMode(const ui::DisplaySnapshot& output,
+               const ui::DisplayMode* mode) override;
+  void Configure(const ui::DisplaySnapshot& output,
+                 const ui::DisplayMode* mode,
+                 const gfx::Point& origin,
+                 const ui::ConfigureCallback& callback) override;
+  void CreateFrameBuffer(const gfx::Size& size) override;
+  void GetHDCPState(const ui::DisplaySnapshot& output,
+                    const ui::GetHDCPStateCallback& callback) override;
+  void SetHDCPState(const ui::DisplaySnapshot& output,
+                    ui::HDCPState state,
+                    const ui::SetHDCPStateCallback& callback) override;
+  std::vector<ui::ColorCalibrationProfile> GetAvailableColorCalibrationProfiles(
+      const ui::DisplaySnapshot& output) override;
+  bool SetColorCalibrationProfile(
+      const ui::DisplaySnapshot& output,
+      ui::ColorCalibrationProfile new_profile) override;
+  bool SetColorCorrection(const ui::DisplaySnapshot& output,
+                          const std::vector<ui::GammaRampRGBEntry>& degamma_lut,
+                          const std::vector<ui::GammaRampRGBEntry>& gamma_lut,
+                          const std::vector<float>& correction_matrix) override;
+  void AddObserver(ui::NativeDisplayObserver* observer) override;
+  void RemoveObserver(ui::NativeDisplayObserver* observer) override;
+  FakeDisplayController* GetFakeDisplayController() override;
+
+ protected:
+  // Initializes display snapshots from command line flags if provided.
+  void InitFromCommandLine();
+
+  // Updates observers when display configuration has changed. Will not update
+  // until after |Initialize()| has been called.
+  void OnConfigurationChanged();
+
+ private:
+  base::ObserverList<ui::NativeDisplayObserver> observers_;
+  std::vector<std::unique_ptr<FakeDisplaySnapshot>> displays_;
+
+  // If |Initialize()| has been called.
+  bool initialized_ = false;
+
+  // The next available display id.
+  uint8_t next_display_id_ = 0;
+
+  DISALLOW_COPY_AND_ASSIGN(FakeDisplayDelegate);
+};
+
+}  // namespace display
+#endif  // UI_DISPLAY_FAKE_DISPLAY_DELEGATE_H_