Add context to gfx::Screen calls in support of simultaneous desktop+ash

ash/display/screen_position_controller.cc

 // Copyright (c) 2012 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.
 
 #include "ash/display/screen_position_controller.h"
 
 #include "ash/display/display_controller.h"
 #include "ash/root_window_controller.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
@@ skipping 44 matching lines @@
 }  // namespace
 
 namespace internal {
 
 void ScreenPositionController::ConvertPointToScreen(
     const aura::Window* window,
     gfx::Point* point) {
   const aura::RootWindow* root = window->GetRootWindow();
   aura::Window::ConvertPointToTarget(window, root, point);
   const gfx::Point display_origin =
-      gfx::Screen::GetDisplayNearestWindow(
+      Shell::GetAshScreen()->GetDisplayNearestWindow(
           const_cast<aura::RootWindow*>(root)).bounds().origin();
   point->Offset(display_origin.x(), display_origin.y());
 }
 
 void ScreenPositionController::ConvertPointFromScreen(
     const aura::Window* window,
     gfx::Point* point) {
   const aura::RootWindow* root = window->GetRootWindow();
   const gfx::Point display_origin =
-      gfx::Screen::GetDisplayNearestWindow(
+      Shell::GetAshScreen()->GetDisplayNearestWindow(
           const_cast<aura::RootWindow*>(root)).bounds().origin();
   point->Offset(-display_origin.x(), -display_origin.y());
   aura::Window::ConvertPointToTarget(root, window, point);
 }
 
 void ScreenPositionController::ConvertNativePointToScreen(
     aura::Window* window,
     gfx::Point* point) {
   std::pair<aura::RootWindow*, gfx::Point> pair =
       wm::GetRootWindowRelativeToWindow(
@@ skipping 57 matching lines @@
 
       // Restore focused/active window.
       if (tracker.Contains(focused))
         window->GetFocusManager()->SetFocusedWindow(focused, NULL);
       else if (tracker.Contains(active))
         activation_client->ActivateWindow(active);
     }
   }
 
   gfx::Point origin(bounds.origin());
-  const gfx::Point display_origin =
-      gfx::Screen::GetDisplayNearestWindow(window).bounds().origin();
+  const gfx::Point display_origin = Shell::GetAshScreen()->
+      GetDisplayNearestWindow(window).bounds().origin();
   origin.Offset(-display_origin.x(), -display_origin.y());
   window->SetBounds(gfx::Rect(origin, bounds.size()));
 }
 
 }  // internal
 }  // ash