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

ash/utility/partial_screenshot_controller.cc

 // Copyright 2014 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/utility/partial_screenshot_controller.h"
 
 #include <cmath>
 
 #include "ash/display/mouse_cursor_event_filter.h"
 #include "ash/screenshot_delegate.h"
 #include "ash/shell.h"
 #include "ash/shell_window_ids.h"
 #include "base/stl_util.h"
 #include "ui/compositor/paint_recorder.h"
 #include "ui/events/event.h"
 #include "ui/events/event_handler.h"
 #include "ui/gfx/canvas.h"
+#include "ui/gfx/screen.h"
 #include "ui/wm/core/cursor_manager.h"
 
 namespace ash {
 
 namespace {
 
 // The size to increase the invalidated area in the layer to repaint. The area
 // should be slightly bigger than the actual region because the region indicator
 // rectangles are drawn outside of the selected region.
 const int kInvalidateRegionAdditionalSize = 3;
@@ skipping 109 matching lines @@
 
 void PartialScreenshotController::StartPartialScreenshotSession(
     ScreenshotDelegate* screenshot_delegate) {
   // Already in a screenshot session.
   if (screenshot_delegate_) {
     DCHECK_EQ(screenshot_delegate_, screenshot_delegate);
     return;
   }
 
   screenshot_delegate_ = screenshot_delegate;
-  Shell::GetScreen()->AddObserver(this);
+  gfx::Screen::GetScreen()->AddObserver(this);
   for (aura::Window* root : Shell::GetAllRootWindows()) {
     layers_[root] = new PartialScreenshotLayer(
         Shell::GetContainer(root, kShellWindowId_OverlayContainer)->layer());
   }
 
   cursor_setter_.reset(new ScopedCursorSetter(
       Shell::GetInstance()->cursor_manager(), ui::kCursorCross));
 
   EnableMouseWarp(false);
 }
@@ skipping 20 matching lines @@
   if (!region.IsEmpty()) {
     screenshot_delegate_->HandleTakePartialScreenshot(
         root_window_, gfx::IntersectRects(root_window_->bounds(), region));
   }
   Cancel();
 }
 
 void PartialScreenshotController::Cancel() {
   root_window_ = nullptr;
   screenshot_delegate_ = nullptr;
-  Shell::GetScreen()->RemoveObserver(this);
+  gfx::Screen::GetScreen()->RemoveObserver(this);
   STLDeleteValues(&layers_);
   cursor_setter_.reset();
   EnableMouseWarp(true);
 }
 
 void PartialScreenshotController::Update(const ui::LocatedEvent& event) {
   // Update may happen without MaybeStart() if the partial screenshot session
   // starts when dragging.
   if (!root_window_)
     MaybeStart(event);
@@ skipping 71 matching lines @@
     return;
   Cancel();
 }
 
 void PartialScreenshotController::OnDisplayMetricsChanged(
     const gfx::Display& display,
     uint32_t changed_metrics) {
 }
 
 }  // namespace ash