[Offline Pages] Remove obsolete synchronous API methods.

components/offline_pages/offline_page_model.h

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_
 #define COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_
 
 #include <stdint.h>
 
 #include <map>
@@ skipping 156 matching lines @@
                               const DeletePageCallback& callback);
 
   // Wipes out all the data by deleting all saved files and clearing the store.
   void ClearAll(const base::Closure& callback);
 
   // Deletes offline pages matching the URL predicate.
   void DeletePagesByURLPredicate(
       const base::Callback<bool(const GURL&)>& predicate,
       const DeletePageCallback& callback);
 
-  // Returns true if there are offline pages in the given |name_space|.  This
-  // method is sync, so the result can be wrong depending on implementation
-  // details of the model.
-  //
-  // Currently, this will return |false| if the model is not loaded, even if
-  // there are pages on disk.
-  bool MaybeHasPages(const std::string& name_space) const;
-
   // Returns true via callback if there are offline pages in the given
   // |name_space|.
   void HasPages(const std::string& name_space,
                 const HasPagesCallback& callback);
 
   // Gets all available offline pages. Requires that the model is loaded.
   void GetAllPages(const GetAllPagesCallback& callback);
 
   // Gets pages that should be removed to clean up storage. Requires that the
   // model is loaded.
@@ skipping 144 matching lines @@
   std::vector<base::Closure> delayed_tasks_;
 
   base::WeakPtrFactory<OfflinePageModel> weak_ptr_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(OfflinePageModel);
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_OFFLINE_PAGE_MODEL_H_