[Offline Pages] Remove load state from public OfflinePageModel API.

components/offline_pages/core/stub_offline_page_model.h

 // Copyright 2016 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_CORE_STUB_OFFLINE_PAGE_MODEL_H_
 #define COMPONENTS_OFFLINE_PAGES_CORE_STUB_OFFLINE_PAGE_MODEL_H_
 
 #include <set>
 #include <string>
 #include <vector>
@@ skipping 39 matching lines @@
       const ClientId& client_id,
       const MultipleOfflineIdCallback& callback) override;
   void GetPageByOfflineId(
       int64_t offline_id,
       const SingleOfflinePageItemCallback& callback) override;
   void GetPagesByURL(
       const GURL& url,
       URLSearchMode url_search_mode,
       const MultipleOfflinePageItemCallback& callback) override;
   ClientPolicyController* GetPolicyController() override;
-  bool is_loaded() const override;
   OfflineEventLogger* GetLogger() override;
 
  private:
   ClientPolicyController policy_controller_;
   std::vector<int64_t> offline_ids_;
 };
 
 }  // namespace offline_pages
 
 #endif  // COMPONENTS_OFFLINE_PAGES_CORE_STUB_OFFLINE_PAGE_MODEL_H_