Remove now-unnecessary wrappers around gfx::Screen::GetScreen()

ash/touch/touch_observer_hud_unittest.cc

 // Copyright (c) 2013 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/touch/touch_observer_hud.h"
 
 #include "ash/ash_switches.h"
 #include "ash/display/display_manager.h"
 #include "ash/root_window_controller.h"
 #include "ash/screen_util.h"
@@ skipping 27 matching lines @@
 
     internal_display_info_ =
         CreateDisplayInfo(internal_display_id_, gfx::Rect(0, 0, 500, 500));
     external_display_info_ =
         CreateDisplayInfo(external_display_id_, gfx::Rect(1, 1, 100, 100));
     mirrored_display_info_ =
         CreateDisplayInfo(mirrored_display_id_, gfx::Rect(0, 0, 100, 100));
   }
 
   gfx::Display GetPrimaryDisplay() {
-    return Shell::GetScreen()->GetPrimaryDisplay();
+    return gfx::Screen::GetScreen()->GetPrimaryDisplay();
   }
 
   const gfx::Display& GetSecondaryDisplay() {
     return ScreenUtil::GetSecondaryDisplay();
   }
 
   void SetupSingleDisplay() {
     display_info_list_.clear();
     display_info_list_.push_back(internal_display_info_);
     GetDisplayManager()->OnNativeDisplaysChanged(display_info_list_);
@@ skipping 522 matching lines @@
 
   SendTouchEventToInternalHud(ui::ET_TOUCH_PRESSED, gfx::Point(10, 10), 1);
   EXPECT_EQ(1, GetInternalTouchPointsCount());
 
   // Disabling projection touch HUD shoud remove it without crashing.
   DisableTouchHudProjection();
   EXPECT_EQ(NULL, GetInternalTouchHudProjection());
 }
 
 }  // namespace ash