Remove the db_loop_ member variable which is a unused following r30163....

chrome/browser/net/chrome_url_request_context.cc

 // Copyright (c) 2009 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.
 
 #include "chrome/browser/net/chrome_url_request_context.h"
 
 #include "base/command_line.h"
 #include "base/string_util.h"
 #include "chrome/browser/browser_process.h"
 #include "chrome/browser/privacy_blacklist/blacklist.h"
@@ skipping 576 matching lines @@
     }
   }
 
   if (profile->GetUserScriptMaster())
     user_script_dir_path_ = profile->GetUserScriptMaster()->user_script_dir();
 
   // TODO(eroman): this doesn't look safe; sharing between IO and UI threads!
   ssl_config_service_ = profile->GetSSLConfigService();
 
   profile_dir_path_ = profile->GetPath();
-
-  // Get references to the database and file threads.
-  db_loop_ = g_browser_process->db_thread()->message_loop();
 }
 
 ChromeURLRequestContextFactory::~ChromeURLRequestContextFactory() {
   CheckCurrentlyOnIOThread();
 }
 
 void ChromeURLRequestContextFactory::ApplyProfileParametersToContext(
     ChromeURLRequestContext* context) {
   // Apply all the parameters. NOTE: keep this in sync with
   // ChromeURLRequestContextFactory(Profile*).
@@ skipping 277 matching lines @@
   return result;
 }
 
 void ChromeURLRequestContextGetter::GetCookieStoreAsyncHelper(
     base::WaitableEvent* completion,
     net::CookieStore** result) {
   // Note that CookieStore is refcounted, yet we do not add a reference.
   *result = GetURLRequestContext()->cookie_store();
   completion->Signal();
 }