Rename ash desktop_background to wallpaper.

ash/wm/session_state_animator_impl.cc

Index: ash/wm/session_state_animator_impl.cc
diff --git a/ash/wm/session_state_animator_impl.cc b/ash/wm/session_state_animator_impl.cc
index ccd8c8e975c3cd3066296b379c8b14823838bd37..fc9f031912e5d620a51b6142b48bbdc04d517f77 100644
--- a/ash/wm/session_state_animator_impl.cc
+++ b/ash/wm/session_state_animator_impl.cc
@@ -30,10 +30,9 @@ const float kPartialFadeRatio = 0.3f;
 const float kMinimumScale = 1e-4f;
 
 // Returns the primary root window's container.
-aura::Window* GetBackground() {
+aura::Window* GetWallpaper() {
   aura::Window* root_window = Shell::GetPrimaryRootWindow();
-  return Shell::GetContainer(root_window,
-                             kShellWindowId_DesktopBackgroundContainer);
+  return Shell::GetContainer(root_window, kShellWindowId_WallpaperContainer);
 }
 
 // Returns the transform that should be applied to containers for the slow-close
@@ -389,9 +388,9 @@ void GetContainersInRootWindow(int container_mask,
     containers->push_back(root_window);
   }
 
-  if (container_mask & SessionStateAnimator::DESKTOP_BACKGROUND) {
-    containers->push_back(Shell::GetContainer(
-        root_window, kShellWindowId_DesktopBackgroundContainer));
+  if (container_mask & SessionStateAnimator::WALLPAPER) {
+    containers->push_back(
+        Shell::GetContainer(root_window, kShellWindowId_WallpaperContainer));
   }
   if (container_mask & SessionStateAnimator::LAUNCHER) {
     containers->push_back(
@@ -411,9 +410,9 @@ void GetContainersInRootWindow(int container_mask,
       }
     }
   }
-  if (container_mask & SessionStateAnimator::LOCK_SCREEN_BACKGROUND) {
+  if (container_mask & SessionStateAnimator::LOCK_SCREEN_WALLPAPER) {
     containers->push_back(Shell::GetContainer(
-        root_window, kShellWindowId_LockScreenBackgroundContainer));
+        root_window, kShellWindowId_LockScreenWallpaperContainer));
   }
   if (container_mask & SessionStateAnimator::LOCK_SCREEN_CONTAINERS) {
     containers->push_back(Shell::GetContainer(
@@ -561,22 +560,22 @@ SessionStateAnimatorImpl::BeginAnimationSequence(base::Closure callback) {
   return new AnimationSequence(this, callback);
 }
 
-bool SessionStateAnimatorImpl::IsBackgroundHidden() const {
-  return !GetBackground()->IsVisible();
+bool SessionStateAnimatorImpl::IsWallpaperHidden() const {
+  return !GetWallpaper()->IsVisible();
 }
 
-void SessionStateAnimatorImpl::ShowBackground() {
+void SessionStateAnimatorImpl::ShowWallpaper() {
   ui::ScopedLayerAnimationSettings settings(
-      GetBackground()->layer()->GetAnimator());
+      GetWallpaper()->layer()->GetAnimator());
   settings.SetTransitionDuration(base::TimeDelta());
-  GetBackground()->Show();
+  GetWallpaper()->Show();
 }
 
-void SessionStateAnimatorImpl::HideBackground() {
+void SessionStateAnimatorImpl::HideWallpaper() {
   ui::ScopedLayerAnimationSettings settings(
-      GetBackground()->layer()->GetAnimator());
+      GetWallpaper()->layer()->GetAnimator());
   settings.SetTransitionDuration(base::TimeDelta());
-  GetBackground()->Hide();
+  GetWallpaper()->Hide();
 }
 
 void SessionStateAnimatorImpl::StartAnimationInSequence(