[Offline Pages] Don't remove user-requested pages when deleting cache.

components/offline_pages/stub_offline_page_model.h

Index: components/offline_pages/stub_offline_page_model.h
diff --git a/components/offline_pages/stub_offline_page_model.h b/components/offline_pages/stub_offline_page_model.h
index d5e0fb80b31c1be0a2999ab587c0ac705f48924d..c08d46a539a8c013665ffe2cec331ad5c1511387 100644
--- a/components/offline_pages/stub_offline_page_model.h
+++ b/components/offline_pages/stub_offline_page_model.h
@@ -32,8 +32,9 @@ class StubOfflinePageModel : public OfflinePageModel {
   void ClearAll(const base::Closure& callback) override;
   void DeletePagesByOfflineId(const std::vector<int64_t>& offline_ids,
                               const DeletePageCallback& callback) override;
-  void DeletePagesByURLPredicate(const UrlPredicate& predicate,
-                                 const DeletePageCallback& callback) override;
+  void DeleteCachedPagesByURLPredicate(
+      const UrlPredicate& predicate,
+      const DeletePageCallback& callback) override;
   void HasPages(const std::string& name_space,
                 const HasPagesCallback& callback) override;
   void CheckPagesExistOffline(