Remove activity_log's Util::DropObsoleteTables().

chrome/browser/extensions/activity_log/counting_policy.cc

 // Copyright 2013 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.
 
 // A policy for storing activity log data to a database that performs
 // aggregation to reduce the size of the database.  The database layout is
 // nearly the same as FullStreamUIPolicy, which stores a complete log, with a
 // few changes:
 //   - a "count" column is added to track how many log records were merged
 //     together into this row
@@ skipping 161 matching lines @@
       retention_time_(base::TimeDelta::FromHours(60)) {
   for (size_t i = 0; i < arraysize(kAlwaysLog); i++) {
     api_arg_whitelist_.insert(
         std::make_pair(kAlwaysLog[i].type, kAlwaysLog[i].name));
   }
 }
 
 CountingPolicy::~CountingPolicy() {}
 
 bool CountingPolicy::InitDatabase(sql::Connection* db) {
-  if (!Util::DropObsoleteTables(db))
-    return false;
-
   if (!string_table_.Initialize(db))
     return false;
   if (!url_table_.Initialize(db))
     return false;
 
   // Create the unified activity log entry table.
   if (!ActivityDatabase::InitializeTable(db,
                                          kTableName,
                                          kTableContentFields,
                                          kTableFieldTypes,
@@ skipping 603 matching lines @@
   return true;
 }
 
 void CountingPolicy::Close() {
   // The policy object should have never been created if there's no DB thread.
   DCHECK(BrowserThread::IsMessageLoopValid(BrowserThread::DB));
   ScheduleAndForget(activity_database(), &ActivityDatabase::Close);
 }
 
 }  // namespace extensions