Extract Favicon Download logic from FaviconTabHelper

chrome/browser/ui/tab_contents/tab_contents.cc

 // 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.
 
 #include "chrome/browser/ui/tab_contents/tab_contents.h"
 
 #include "base/command_line.h"
 #include "base/lazy_instance.h"
 #include "chrome/browser/autofill/autofill_external_delegate.h"
 #include "chrome/browser/autofill/autofill_manager.h"
 #include "chrome/browser/automation/automation_tab_helper.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
 #include "chrome/browser/extensions/api/web_navigation/web_navigation_api.h"
 #include "chrome/browser/extensions/tab_helper.h"
 #include "chrome/browser/external_protocol/external_protocol_observer.h"
+#include "chrome/browser/favicon/favicon_download_helper.h"
 #include "chrome/browser/favicon/favicon_tab_helper.h"
 #include "chrome/browser/history/history_tab_helper.h"
 #include "chrome/browser/infobars/infobar_tab_helper.h"
 #include "chrome/browser/net/load_time_stats.h"
 #include "chrome/browser/omnibox_search_hint.h"
 #include "chrome/browser/password_manager/password_manager.h"
 #include "chrome/browser/password_manager/password_manager_delegate_impl.h"
 #include "chrome/browser/pepper_broker_observer.h"
 #include "chrome/browser/plugins/plugin_observer.h"
 #include "chrome/browser/prerender/prerender_tab_helper.h"
@@ skipping 98 matching lines @@
   }
   BlockedContentTabHelper::CreateForWebContents(contents);
   BookmarkTabHelper::CreateForWebContents(contents);
   chrome_browser_net::LoadTimeStatsTabHelper::CreateForWebContents(contents);
   ConstrainedWindowTabHelper::CreateForWebContents(contents);
   CoreTabHelper::CreateForWebContents(contents);
   extensions::TabHelper::CreateForWebContents(contents);
   extensions::WebNavigationTabObserver::CreateForWebContents(contents);
   ExternalProtocolObserver::CreateForWebContents(contents);
   FaviconTabHelper::CreateForWebContents(contents);
+  FaviconDownloadHelper::CreateForWebContentsAndDelegate(contents,
+      FaviconTabHelper::FromWebContents(contents));

[sky, 2012/10/24 16:38:10]

Doesn't doing this lead to the possibility of FaviconTabHelper being destroyed
before FaviconDownloadHelper?

[Cait (Slow), 2012/10/24 17:31:20]

That is a possibility. The FaviconDownloadHelper only keeps a weak pointer to
its delegate, though. 

The other option would be to have a separate SetDelegate method, but seeing as
the FaviconDownloadHelper's  main purpose is to relay data back to the delegate,
there is not much point in creating an instance of it without a delegate...

   FindTabHelper::CreateForWebContents(contents);
   HistoryTabHelper::CreateForWebContents(contents);
   HungPluginTabHelper::CreateForWebContents(contents);
   InfoBarTabHelper::CreateForWebContents(contents);
   MetroPinTabHelper::CreateForWebContents(contents);
   NavigationMetricsRecorder::CreateForWebContents(contents);
   PasswordManagerDelegateImpl::CreateForWebContents(contents);
   PasswordManager::CreateForWebContentsAndDelegate(
       contents, PasswordManagerDelegateImpl::FromWebContents(contents));
   PepperBrokerObserver::CreateForWebContents(contents);
@@ skipping 78 matching lines @@
 
 ////////////////////////////////////////////////////////////////////////////////
 // WebContentsObserver overrides
 
 void TabContents::WebContentsDestroyed(WebContents* tab) {
   // Destruction of the WebContents should only be done by us from our
   // destructor. Otherwise it's very likely we (or one of the helpers we own)
   // will attempt to access the WebContents and we'll crash.
   DCHECK(in_destructor_);
 }