autocomplete: Add AutocompleteProvider::Type enum.

chrome/browser/ui/app_list/search_builder.h

Index: chrome/browser/ui/app_list/search_builder.h
diff --git a/chrome/browser/ui/app_list/search_builder.h b/chrome/browser/ui/app_list/search_builder.h
index f5f2d26d91eff08262143764fbc305afc64cef2a..314cc286938a4aea24039bf43258aa58517dc3bc 100644
--- a/chrome/browser/ui/app_list/search_builder.h
+++ b/chrome/browser/ui/app_list/search_builder.h
@@ -19,7 +19,6 @@ class SearchResult;
 class AppListController;
 class AutocompleteController;
 class AutocompleteResult;
-class ExtensionAppProvider;
 class Profile;
 
 // SearchBuilder creates app list search results via AutoCompleteController.
@@ -63,10 +62,6 @@ class SearchBuilder : public AutocompleteControllerDelegate {
   // The controller of the app list. Owned by the app list delegate.
   AppListController* list_controller_;
 
-  // ExtensionAppProvider used for apps only mode. If apps only mode becomes the
-  // only mode, remove the AutocompleteController above. Otherwise, remove this.
-  scoped_refptr<ExtensionAppProvider> apps_provider_;
-
   DISALLOW_COPY_AND_ASSIGN(SearchBuilder);
 };