Start to decouple display::Display from ws::PlatformDisplay.

services/ui/ws/platform_display_default.h

Index: services/ui/ws/platform_display_default.h
diff --git a/services/ui/ws/platform_display_default.h b/services/ui/ws/platform_display_default.h
index 04252ee221912b8e7b53906235498b488aa353d3..399594c03f9db6f83a73254dde4854c76a6cbd0c 100644
--- a/services/ui/ws/platform_display_default.h
+++ b/services/ui/ws/platform_display_default.h
@@ -13,6 +13,7 @@
 #include "services/ui/ws/frame_generator_delegate.h"
 #include "services/ui/ws/platform_display.h"
 #include "services/ui/ws/platform_display_delegate.h"
+#include "services/ui/ws/server_window.h"
 #include "ui/platform_window/platform_window_delegate.h"
 
 namespace ui {
@@ -29,12 +30,12 @@ class PlatformDisplayDefault : public PlatformDisplay,
                                public ui::PlatformWindowDelegate,
                                public FrameGeneratorDelegate {
  public:
-  explicit PlatformDisplayDefault(const PlatformDisplayInitParams& init_params);
+  PlatformDisplayDefault(ServerWindow* root_window,
+                         const display::ViewportMetrics& metrics);
   ~PlatformDisplayDefault() override;
 
   // PlatformDisplay:
   void Init(PlatformDisplayDelegate* delegate) override;
-  int64_t GetId() const override;
   void SetViewportSize(const gfx::Size& size) override;
   void SetTitle(const base::string16& title) override;
   void SetCapture() override;
@@ -42,9 +43,7 @@ class PlatformDisplayDefault : public PlatformDisplay,
   void SetCursorById(mojom::Cursor cursor) override;
   void UpdateTextInputState(const ui::TextInputState& state) override;
   void SetImeVisibility(bool visible) override;
-  gfx::Rect GetBounds() const override;
   bool UpdateViewportMetrics(const display::ViewportMetrics& metrics) override;
-  const display::ViewportMetrics& GetViewportMetrics() const override;
   gfx::AcceleratedWidget GetAcceleratedWidget() const override;
   FrameGenerator* GetFrameGenerator() override;
 
@@ -72,7 +71,7 @@ class PlatformDisplayDefault : public PlatformDisplay,
   // FrameGeneratorDelegate:
   bool IsInHighContrastMode() override;
 
-  const int64_t display_id_;
+  ServerWindow* root_window_;
 
 #if !defined(OS_ANDROID)
   std::unique_ptr<ui::ImageCursors> image_cursors_;
@@ -84,7 +83,6 @@ class PlatformDisplayDefault : public PlatformDisplay,
   display::ViewportMetrics metrics_;
   std::unique_ptr<ui::PlatformWindow> platform_window_;
   gfx::AcceleratedWidget widget_;
-  ServerWindow* root_window_;
   float init_device_scale_factor_;
 
   DISALLOW_COPY_AND_ASSIGN(PlatformDisplayDefault);