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

ash/shell.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/shell.h"
 
 #include <algorithm>
 #include <string>
 
 #include "ash/accelerators/focus_manager_factory.h"
@@ skipping 175 matching lines @@
       delegate_(delegate),
 #if defined(OS_CHROMEOS)
       output_configurator_(new chromeos::OutputConfigurator()),
       output_configurator_animation_(
           new internal::OutputConfiguratorAnimation()),
 #endif  // defined(OS_CHROMEOS)
       shelf_(NULL),
       panel_layout_manager_(NULL),
       status_area_widget_(NULL),
       browser_context_(NULL) {
-  gfx::Screen::SetInstance(screen_);
+  gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_NATIVE, screen_);
+  gfx::Screen::SetScreenInstance(gfx::SCREEN_TYPE_ALTERNATE, screen_);
   ui_controls::InstallUIControlsAura(internal::CreateUIControls());
 #if defined(OS_CHROMEOS)
   output_configurator_->AddObserver(output_configurator_animation_.get());
   base::MessagePumpAuraX11::Current()->AddDispatcherForRootWindow(
       output_configurator());
 #endif  // defined(OS_CHROMEOS)
 }
 
 Shell::~Shell() {
   views::FocusManagerFactory::Install(NULL);
@@ skipping 122 matching lines @@
 aura::RootWindow* Shell::GetPrimaryRootWindow() {
   return GetInstance()->display_controller()->GetPrimaryRootWindow();
 }
 
 // static
 aura::RootWindow* Shell::GetActiveRootWindow() {
   return GetInstance()->active_root_window_;
 }
 
 // static
+gfx::Screen* Shell::GetScreen() {
+  return gfx::Screen::GetScreenFor(GetPrimaryRootWindow());
+}
+
+// static
 Shell::RootWindowList Shell::GetAllRootWindows() {
   return Shell::GetInstance()->display_controller()->
       GetAllRootWindows();
 }
 
 // static
 aura::Window* Shell::GetContainer(aura::RootWindow* root_window,
                                   int container_id) {
   return root_window->GetChildById(container_id);
 }
@@ skipping 473 matching lines @@
        iter != controllers.end(); ++iter) {
     if ((*iter)->GetSystemModalLayoutManager()->
             CanWindowReceiveEvents(window)) {
       return true;
     }
   }
   return false;
 }
 
 }  // namespace ash