Eliminate the archived history database and clean up related code.

chrome/browser/history/history_backend.h

Index: chrome/browser/history/history_backend.h
diff --git a/chrome/browser/history/history_backend.h b/chrome/browser/history/history_backend.h
index 019adb8e4be585a2975c72a8c46cd8b58ad0d392..ebae0b0eca3ec17694039be1f121756eb959bdc9 100644
--- a/chrome/browser/history/history_backend.h
+++ b/chrome/browser/history/history_backend.h
@@ -15,7 +15,6 @@
 #include "base/gtest_prod_util.h"
 #include "base/memory/memory_pressure_listener.h"
 #include "base/memory/scoped_ptr.h"
-#include "chrome/browser/history/archived_database.h"
 #include "chrome/browser/history/expire_history_backend.h"
 #include "chrome/browser/history/history_database.h"
 #include "chrome/browser/history/history_marshaling.h"
@@ -607,11 +606,8 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   // The *Text() version performs a brute force query of the history DB to
   // search for results which match the given text query.
   // Both functions assume QueryHistory already checked the DB for validity.
-  void QueryHistoryBasic(URLDatabase* url_db, VisitDatabase* visit_db,
-                         const QueryOptions& options, QueryResults* result);
-  void QueryHistoryText(URLDatabase* url_db,
-                        VisitDatabase* visit_db,
-                        const base::string16& text_query,
+  void QueryHistoryBasic(const QueryOptions& options, QueryResults* result);
+  void QueryHistoryText(const base::string16& text_query,
                         const QueryOptions& options,
                         QueryResults* result);
 
@@ -768,7 +764,7 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
       scoped_ptr<HistoryDetails> details) OVERRIDE;
   virtual void NotifySyncURLsModified(URLRows* rows) OVERRIDE;
   virtual void NotifySyncURLsDeleted(bool all_history,
-                                     bool archived,
+                                     bool expired,
                                      URLRows* rows) OVERRIDE;
 
   // Deleting all history ------------------------------------------------------
@@ -776,9 +772,9 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   // Deletes all history. This is a special case of deleting that is separated
   // from our normal dependency-following method for performance reasons. The
   // logic lives here instead of ExpireHistoryBackend since it will cause
-  // re-initialization of some databases such as Thumbnails or Archived that
-  // could fail. When these databases are not valid, our pointers must be NULL,
-  // so we need to handle this type of operation to keep the pointers in sync.
+  // re-initialization of some databases (e.g. Thumbnails) that could fail.
+  // When these databases are not valid, our pointers must be NULL, so we need
+  // to handle this type of operation to keep the pointers in sync.
   void DeleteAllHistory();
 
   // Given a vector of all URLs that we will keep, removes all thumbnails
@@ -821,9 +817,6 @@ class HistoryBackend : public base::RefCountedThreadSafe<HistoryBackend>,
   bool scheduled_kill_db_;  // Database is being killed due to error.
   scoped_ptr<ThumbnailDatabase> thumbnail_db_;
 
-  // Stores old history in a larger, slower database.
-  scoped_ptr<ArchivedDatabase> archived_db_;
-
   // Manages expiration between the various databases.
   ExpireHistoryBackend expirer_;