Rename ash desktop_background to wallpaper.

ash/wm/system_wallpaper_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/wm/system_background_controller.h"
+#include "ash/wm/system_wallpaper_controller.h"
 
 #include "ui/aura/window.h"
 #include "ui/compositor/layer.h"
 #include "ui/compositor/layer_type.h"
 
 namespace ash {
 
-SystemBackgroundController::SystemBackgroundController(
-    aura::Window* root_window,
-    SkColor color)
+SystemWallpaperController::SystemWallpaperController(aura::Window* root_window,
+                                                     SkColor color)
     : root_window_(root_window), layer_(new ui::Layer(ui::LAYER_SOLID_COLOR)) {
   root_window_->AddObserver(this);
   layer_->SetColor(color);
 
   ui::Layer* root_layer = root_window_->layer();
   layer_->SetBounds(gfx::Rect(root_layer->bounds().size()));
   root_layer->Add(layer_.get());
   root_layer->StackAtBottom(layer_.get());
 }
 
-SystemBackgroundController::~SystemBackgroundController() {
+SystemWallpaperController::~SystemWallpaperController() {
   root_window_->RemoveObserver(this);
 }
 
-void SystemBackgroundController::SetColor(SkColor color) {
+void SystemWallpaperController::SetColor(SkColor color) {
   layer_->SetColor(color);
 }
 
-void SystemBackgroundController::OnWindowBoundsChanged(
+void SystemWallpaperController::OnWindowBoundsChanged(
     aura::Window* root,
     const gfx::Rect& old_bounds,
     const gfx::Rect& new_bounds) {
   DCHECK_EQ(root_window_, root);
   layer_->SetBounds(gfx::Rect(root_window_->layer()->bounds().size()));
 }
 
 }  // namespace ash