Don't treat back/forwards as typed transitions in history.

components/history/core/browser/history_backend.h

 // Copyright (c) 2012 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_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 #define COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_
 
 #include <set>
 #include <string>
 #include <utility>
@@ skipping 448 matching lines @@
   friend class HistoryBackendDBTest;  // So the unit tests can poke our innards.
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteAll);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteAllThenAddData);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPagesWithDetails);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, UpdateURLs);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, ImportedFaviconsTest);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, URLsNoLongerBookmarked);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, StripUsernamePasswordTest);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, DeleteThumbnailsDatabaseTest);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageVisitSource);
+  FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageVisitBackForward);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageVisitNotLastVisit);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
                            AddPageVisitFiresNotificationWithCorrectDetails);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddPageArgsSource);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, AddVisitsSource);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, GetMostRecentVisits);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, RemoveVisitsSource);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, RemoveVisitsTransitions);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest, MigrationVisitSource);
   FRIEND_TEST_ALL_PREFIXES(HistoryBackendTest,
@@ skipping 344 matching lines @@
 
   // List of observers
   ObserverList<HistoryBackendObserver> observers_;
 
   DISALLOW_COPY_AND_ASSIGN(HistoryBackend);
 };
 
 }  // namespace history
 
 #endif  // COMPONENTS_HISTORY_CORE_BROWSER_HISTORY_BACKEND_H_