Adds GetDisplays() to WindowManager

ui/mojo/init/ui_init.h

 // Copyright 2015 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_MOJO_INIT_UI_INIT_H_
 #define UI_MOJO_INIT_UI_INIT_H_
 
+#include <vector>
+
 #include "base/basictypes.h"
 #include "base/callback_forward.h"
 #include "base/memory/scoped_ptr.h"
 
 namespace gfx {
+class Display;
 class Screen;
-class Size;
 }
 
 namespace ui {
 class GestureConfiguration;
 
 namespace mojo {
 
 class GestureConfigurationMojo;
 
 // UIInit configures any state needed by apps that make use of ui classes (not
 // including aura).
 class UIInit {
  public:
-  UIInit(const gfx::Size& screen_size_in_pixels, float device_pixel_ratio);
+  explicit UIInit(const std::vector<gfx::Display>& displays);
   ~UIInit();
 
  private:
   scoped_ptr<gfx::Screen> screen_;
 #if defined(OS_ANDROID)
   scoped_ptr<GestureConfigurationMojo> gesture_configuration_;
 #endif
 
   DISALLOW_COPY_AND_ASSIGN(UIInit);
 };
 
 }  // namespace mojo
 }  // namespace ui
 
 #endif  // UI_MOJO_INIT_UI_INIT_H_