Disable Set wallpaper option in context menu for guest user instead of remove it

ash/shell_context_menu.cc

Index: ash/shell_context_menu.cc
diff --git a/ash/shell_context_menu.cc b/ash/shell_context_menu.cc
index 4c0ab852a45aeb922efbf535fe0f7d66332e4da2..dc67f842e64992f9e21b824954e689425cb2e5e4 100644
--- a/ash/shell_context_menu.cc
+++ b/ash/shell_context_menu.cc
@@ -22,9 +22,6 @@ ShellContextMenu::~ShellContextMenu() {
 
 void ShellContextMenu::ShowMenu(views::Widget* widget,
                                 const gfx::Point& location) {
-  if (!Shell::GetInstance()->user_wallpaper_delegate()->
-      CanOpenSetWallpaperPage())
-    return;
   ui::SimpleMenuModel menu_model(this);
   menu_model.AddItem(MENU_CHANGE_WALLPAPER,
       l10n_util::GetStringUTF16(IDS_AURA_SET_DESKTOP_WALLPAPER));
@@ -42,7 +39,17 @@ bool ShellContextMenu::IsCommandIdChecked(int command_id) const {
 }
 
 bool ShellContextMenu::IsCommandIdEnabled(int command_id) const {
-  return true;
+  switch (static_cast<MenuItem>(command_id)) {
+    case MENU_CHANGE_WALLPAPER: {
+      if (Shell::GetInstance()->user_wallpaper_delegate()->

[sky, 2012/04/12 16:08:35]

nit: no need for the conditional:
  return Shell::GetInstance()->user_wallpaper_delegate()...
does what you want.

[bshe, 2012/04/12 17:49:55]

Done.

+          CanOpenSetWallpaperPage())
+        return true;
+      else
+        return false;
+    }
+    default:
+      return true;
+  }
 }
 
 void ShellContextMenu::ExecuteCommand(int command_id) {