Update some uses of Value in chrome/browser to use the base:: namespace.

chrome/browser/chromeos/login/wallpaper_manager.cc

Index: chrome/browser/chromeos/login/wallpaper_manager.cc
diff --git a/chrome/browser/chromeos/login/wallpaper_manager.cc b/chrome/browser/chromeos/login/wallpaper_manager.cc
index 3e4f919bf59d00db404ee7a886c04698281c26d3..e19da348938283c3090cc69d5cb33b4f0fd57bc2 100644
--- a/chrome/browser/chromeos/login/wallpaper_manager.cc
+++ b/chrome/browser/chromeos/login/wallpaper_manager.cc
@@ -855,8 +855,9 @@ bool WallpaperManager::GetUserWallpaperInfo(const std::string& email,
     return true;
   }
 
-  const DictionaryValue* user_wallpapers = g_browser_process->local_state()->
-      GetDictionary(prefs::kUsersWallpaperInfo);
+  const base::DictionaryValue* user_wallpapers =
+      g_browser_process->local_state()->
+          GetDictionary(prefs::kUsersWallpaperInfo);
   const base::DictionaryValue* wallpaper_info_dict;
   if (user_wallpapers->GetDictionaryWithoutPathExpansion(
           email, &wallpaper_info_dict)) {