Moved ExtensionPrefs and related into extensions namespace

chrome/browser/extensions/extension_sorting.h

Index: chrome/browser/extensions/extension_sorting.h
diff --git a/chrome/browser/extensions/extension_sorting.h b/chrome/browser/extensions/extension_sorting.h
index 7ce97e32b31ab00e86ccda59161a771aaeb21e6a..13db0e8dbb7bc48e1ed4c39c9b20b3ff952ea1e0 100644
--- a/chrome/browser/extensions/extension_sorting.h
+++ b/chrome/browser/extensions/extension_sorting.h
@@ -29,7 +29,8 @@ class ExtensionSorting {
 
   // Properly initialize ExtensionSorting internal values that require
   // |extension_ids|.
-  void Initialize(const ExtensionPrefs::ExtensionIdSet& extension_ids);
+  void Initialize(
+      const extensions::ExtensionPrefs::ExtensionIdSet& extension_ids);
 
   // Resolves any conflicts the might be created as a result of syncing that
   // results in two icons having the same page and app launch ordinal. After
@@ -119,10 +120,11 @@ class ExtensionSorting {
   // Initialize the |page_ordinal_map_| with the page ordinals used by the
   // given extensions.
   void InitializePageOrdinalMap(
-      const ExtensionPrefs::ExtensionIdSet& extension_ids);
+      const extensions::ExtensionPrefs::ExtensionIdSet& extension_ids);
 
   // Migrates the app launcher and page index values.
-  void MigrateAppIndex(const ExtensionPrefs::ExtensionIdSet& extension_ids);
+  void MigrateAppIndex(
+      const extensions::ExtensionPrefs::ExtensionIdSet& extension_ids);
 
   // Called to add a new mapping value for |extension_id| with a page ordinal
   // of |page_ordinal| and a app launch ordinal of |app_launch_ordinal|. This