[Offline pages] Extracting AddRequest method in RequestQueueStore

components/offline_pages/offline_page_types.h

Index: components/offline_pages/offline_page_types.h
diff --git a/components/offline_pages/offline_page_types.h b/components/offline_pages/offline_page_types.h
index 20d0d99837104db7f3a06d704c64b996f247620c..d80c0feb09be13098a441aafb94d35281be862c7 100644
--- a/components/offline_pages/offline_page_types.h
+++ b/components/offline_pages/offline_page_types.h
@@ -57,11 +57,12 @@ enum class DeletePageResult {
   RESULT_COUNT,
 };
 
-// Result of loading all pages.
-enum class LoadResult {
+// Statuses referring to actions taken on items in the stores.
+enum class ItemActionStatus {
   SUCCESS,
-  CANCELLED,
-  STORE_FAILURE,
+  ALREADY_EXISTS,
+  NOT_FOUND,
+  STORE_ERROR,
 };
 
 typedef std::set<GURL> CheckPagesExistOfflineResult;